Best Thyroid Supplements (2021) Review Top Thyroid

Chicago, IL, April 23, 2021 (GLOBE NEWSWIRE) — The thyroid is a small organ in the neck that produces hormones essential for maintaining healthy energy levels, weight mood, and many other bodily functions. A thyroid that is overactive or underactive can have a significant negative impact on your health, causing fatigue, weakness, mood disorders, and weight gain.

Thyroid supplements are designed to support the healthy function of your thyroid. While there are prescription drugs designed to treat thyroid disease, thyroid supplements are meant to support the function of the thyroid in healthy adults.

After hours of research into hundreds of thyroid supplements, we’ve discovered the best thyroid supplements for 2021 to help your thyroid function as optimally as possible.

The Rankings

#1 – 1 Body Thyroid Support

1 Body Thyroid Support is our top-rated thyroid supplement for 2021. It contains a high dose of the most important vitamins & minerals needed for optimal thyroid function as well as some of the most clinically studied herbal extracts.

In addition, 1 Body added the most essential minerals in a unique form called a chelate. This provides you with a more bioavailable form of minerals so your body can absorb the minerals more efficiently.

Besides vitamins & minerals, 1 Body Thyroid Support contains herbal ingredients like kelp, forskolin, and ashwagandha root, all three of which have demonstrated some ability to improve thyroid function.

#2 – PhytAge Labs Thyroid Rescue 911

PhytAge Labs Thyroid Rescue 911 has a potent combination of essential vitamins and minerals, along with several scientifically-backed herbal extracts.

Vitamin B-12, iodine, zinc, and magnesium are some of the essential vitamins and minerals in Thyroid Rescue. Other herbal extracts like ashwagandha, bladderwrack, cayenne pepper, and kelp are also added for further support.

Overall, Thyroid Rescue 911 contains the best of both worlds with a dozen proven ingredients that support thyroid function. It’s a solid product backed by a long 90-day money-back guarantee and well worth trying to for thyroid support.

#3 – Vitapost Thyroid Support

Vitapost Thyroid support is another excellent thyroid supplement that uses six main ingredients to support thyroid function. These ingredients include iodine, vitamin B-12, selenium, L-tyrosine, zinc, and ashwagandha.

All six of these ingredients have been clinically studied and proven to support thyroid function in some manner and Vitapost Thyroid Support is one of the most popular thyroid products on the market.

#4 – Healths Harmony Thyroid Support

Healths Harmony Thyroid Support is a complete thyroid supplement that combines iodine along with some of the most important trace minerals for thyroid function.

You can expect to see the usual minerals in Healths Harmony like zinc, copper, and selenium, but they’ve also added manganese and magnesium. Some herbal extracts like cayenne pepper, ashwagandha, and kelp were also added for further thyroid support.

#5 – Zhou Nutrition Thyroid Support

Zhou Nutrition Thyroid Support is one of the best-selling thyroid supplements on Amazon. It has a large number of essential vitamins and minerals needed to keep your thyroid healthy.

It contains an ideal dose of iodine derived from Atlantic kelp, which is essential for synthesizing hormones. It also contains vitamin b12 to support healthy energy levels, along with selenium, copper, and manganese.

Finally, there are a few herbal extracts like ashwagandha root powder, cayenne pepper, and schizandra. All three are said to support your metabolism, improve focus, and enhance energy levels.

#6 – PhysioTru

PhysioTru is less of a thyroid supplement and more of an anti-inflammatory and probiotic supplement that also boosts thyroid function.

It’s made with 56 prebiotic foods, 8 probiotic foods, curcumin, and piperine and although these ingredients aren’t known for thyroid support, they still can support the thyroid function.

This is because PhysioTru eliminates the inflammation that interferes with your thyroid. The prebiotic ingredients also feed your gut flora, which are healthy bacteria that aid in digestion and nutrient absorption.

Although it’s not a traditional thyroid supplement, the results have spoken for themselves. Thousands of people attest to PhysioTru and that makes it a supplement worth trying.

#7- Pure Encapsulations Thyroid Support Complex

Pure Encapsulations Thyroid Support Complex is unique in that it is derived more so from herbal extracts than vitamins and minerals.

The main ingredients include ashwagandha, forskolin, gum resin, turmeric, and L-tyrosine. Ashwagandha has the most evidence regarding thyroid support but forskolin and tyrosine have also demonstrated an ability to improve thyroid function.

In addition to these herbal extracts, Pure Encapsulations included vitamin A, C, D, iodine, zinc, and selenium to their thyroid product, which is overall a solid thyroid supplement.

#8 – VitaStrength Thyroid Support Complete Formula

VitaStrength combines the best of both worlds with a complete blend of vitamins, minerals, and herbal extracts. Essential vitamins & minerals like magnesium, vitamin B, iodine, copper, and manganese are included, along with proven herbal extracts like ashwagandha, kelp, & cayenne.

The big selling point for VitaStrength is that it is one of the most affordable thyroid supplements. While many products come in at $20-30 for one bottle, VitaStrength only will cost you around $12 per bottle. Plus, it has all the essentials for thyroid support, which makes it a solid choice.

#9– LES Labs Thyroid Support

Unlike most other thyroid supplements, LES Labs focuses almost entirely on the vitamin and minerals that support thyroid function.

Aside from ashwagandha (which is perhaps the best known herbal extract for thyroid function), there are no other herbal extracts in LES Labs Thyroid Support. Instead, LES Labs contains vitamin B, C, E, iodine, and the other trace minerals that are virtually in every other thyroid product.

#10 – Optimox Iodoral

Optimox Iodoral is a high potency iodine and potassium supplement for thyroid support. It may be the ideal product for individuals suffering from poor thyroid function due to low iodine levels.

If you need a more potent supplement for thyroid function, you may want to look elsewhere. If iodine is the reason for your inefficient thyroid function, then Iodoral is a great option.

Bonus #1 – The Hypothyroidism Solution

The Hypothyroidism Solution is not a supplement but a program designed to reset your thyroid by eliminating inflammation and toxins from your body. The program claims to show you exactly what you need to eat and what to do to restore healthy thyroid function.

If you’re someone who doesn’t want to take a bunch of pills and instead wants to make natural changes to your life to restore thyroid function, then this digital program may be right for you.

Bonus #2 – Thyroid Factor

Thyroid Factor is a 21-day program specifically designed for women to boost thyroid function and to lose weight. The program claims to tell women how to regain thyroid function, what foods to avoid, the thyroid questions women need to ask their doctor, and what other supplements to take.

If you’re a woman who is unsure what exactly you need to do to regain thyroid function, then this program is probably a good program worth buying. It will help hold your hand to help you make the changes you need to restore thyroid function and the supplements most essential to keep your thyroid functioning properly.

Who Needs a Thyroid Supplement?

The main function of thyroid supplements is to provide you with essential vitamins and minerals that support your thyroid. This is not to say that thyroid supplements can replace a prescription thyroid medication because these supplements do not actually contain thyroid hormones needed to prevent serious health issues.

If you’re on prescription medication, you should absolutely stay on your medication and let your doctor know you plan on taking a supplement as well.

However, if you feel like your thyroid has slowed, is slowing, or isn’t operating as efficiently as it has been, you may benefit from a thyroid supplement. There are clear signs of poor thyroid function, which include:

• Frequent to constant fatigue and tiredness
• Sudden weight gain
• Thinning hair
• Poor cognitive function
• Muscle weakness, aches, tenderness, and stiffness
• Depression
• Pain, stiffness, & swelling in joints

If you experience some or many of these health issues, then there is a good chance that your thyroid isn’t functioning as well as it should be. Taking a thyroid supplement may help to stop these symptoms and even reverse them after some time.

Get the #1 Best Ranked Thyroid Supplement for Real Thyroid Health Benefits and Results in 2021 Today

How We Ranked

While prescription drugs contain active forms of thyroid hormones, we wanted to exclude any product with these hormones. Instead, we focused on supplements that had ingredients that provide the greatest chance for improved thyroid function with the lowest risk for adverse health effects.

We researched hundreds of thyroid supplements on various marketplaces and we based our top rankings based on these factors:

Ingredient Formula & Dosage

We primarily focused on supplements that contained the most essential vitamins and minerals needed for proper thyroid. We looked for supplements that contained iodine and B-vitamins, as well as vitamin A, C, and zinc.

Products with other important trace minerals like selenium, copper, and magnesium were also given higher rankings since these minerals have demonstrated some ability to improve thyroid function.

We also evaluated supplements with certain herbal extracts like ashwagandha & cayenne pepper because these herbal extracts have shown an ability to improve thyroid function in clinical studies. While we focused more so on the vitamin & mineral combination, we still rated products higher that also contained these herbal extracts since they were seen as stronger products.

Once we investigated the ingredients in each product, we looked at the individual dosage. For example, we wanted products that contained a dosage in the range of 125 to 200mcg of iodine per day, which is the ideal range for thyroid function. Some products contained upwards of 1,000 mcg per day, which may potentially be dangerous.

Likewise, ashwagandha is commonly added to thyroid products and is safe around the 400-800mg dosage per day. Therefore, we searched for products within that range and excluded products that contained a much higher dosage because we couldn’t guarantee that the dosage is safe.

Product Quality & Standards

After investigating the formula and dosage of each product, we researched the product quality and standards used to manufacture each product.

We instantly eliminated products that used fillers, binders, or extra ingredients like silicon dioxide or magnesium stearate. These binders & fillers are often unnecessary and only added to make a product cheaper in price. Plus, then can be dangerous in some cases. We only wanted products with active, safe ingredients.

Finally, we made sure that we only listed products that were manufactured using good manufacturing practices (GMP) in an FDA-registered facility. These facilities have to adhere to stricter standards and practices and manufacture safer, higher quality products in most instances.

Customer Reviews

Finally, the last step in our process was to look at real customer reviews. There’s no better way to evaluate a product than to get in the mind of the actual customers, so we considered the # of reviews, the % of positive reviews, overall rating, and overall sentiment of each product.

While a few bad reviews weren’t a deal-breaker, we still gave products with a greater amount of positive reviews high rankings than those with only a few reviews. If for example product A had fewer reviews than product B – but had reviews dating back twice as long as product B, we considered that for our rankings.

Overall, we tried to get the most popular, proven products that customers actually liked. This is why we are extremely confident in our rankings and believe our top thyroid products can truly enable your thyroid to function better.

(HUGE SAVINGS TODAY) Save Big on the #1 Top Ranked Thyroid Supplement for Thyroid Health Support

Scientific Evidence

Although thyroid supplements contain essential vitamins and minerals needed to support thyroid function – individual supplements haven’t actually been tested. So what does science say about the popular ingredients in thyroid supplements?

Supplements containing iodine can improve your thyroid function. Iodine is a trace mineral that is lacking in a large percentage in the diet of the adult population. It is directly linked to thyroid function.

Iodine is a necessary precursor for the production of many thyroid hormones. When iodine intake isn’t where it needs to be, thyroid function suffers. This was proven in a scientific review published by Hye Rim Chung in South Korea.

In his review, Chung evaluates a large pile of data that suggests the insufficient consumption of iodine can cause thyroid issues. Adding iodine supplements seemed to reverse those effects.

Selenium is important for thyroid function. Selenium is a trace mineral that isn’t found in many foods. Research shows it plays a large role in thyroid function.

German scientists found that selenium protects thyroid cells during the manufacturing process of thyroid hormones. This process causes the body to create hydrogen peroxide as a byproduct – and if undealt with, it can be highly destructive.

Selenium protects these cells from being damaged and researchers have found that the highest concentration of selenium is found in the thyroid, highlighting selenium’s importance there.

Ashwagandha is a popular herbal extract that can potentially directly increase thyroid hormone concentrations. Up until this point, few herbal extracts have demonstrated a clear ability to improve thyroid function. The exception is ashwagandha.

According to several published studies, ashwagandha may have a strong effect on thyroid function. In a 2001 paper published in the Journal of Pharmacy and Pharmacology, lab mice were given ashwagandha extract.

After just 20 days, researchers found that T3 and T4 thyroid hormone levels were significantly higher in the ashwagandha group. They noted that the supplement also appeared to have a protective effect on liver function in mice.

Copper, zinc, and vitamin B are also essential for thyroid function. Although the role of trace minerals like zinc and copper are not as well-known as selenium in regards to thyroid function, medical experts agree – they are essential.

It is believed that may make the process of producing thyroid hormones easier but researchers haven’t been able to identify the exact mechanism behind this.

(LOWEST PRICE ONLINE) Get the Best Thyroid Supplement Directly from the Official Website for the Biggest Discount

Side Effects & Dosage

While prescription thyroid medications often have several side effects, thyroid supplement side effects are less known and are more complex. That’s because prescription medications contain active thyroid hormones, which can alter your body’s biochemistry and potentially negatively impact you.

In general, there are zero side effects to taking thyroid supplements because they contain the most essential vitamins needed for thyroid function. When dosed properly, there are no real risks for adverse effects.

When herbal extracts are included, things can get more complicated. Ashwagandha can cause issues when an excessive dosage is taken, which is why a recommended dosage of 400-800mg a day is ideal. In general, though, these herbal extracts pose no risk to your health.

Recommended dosage

The most important dosage to look at is the amount of iodine in your thyroid supplement.

According to the National Institutes of Health, a dosage of 150 to 220mcg (micrograms) is recommended per day. Pregnant or nursing mothers can increase this dosage up to around 300mcg per day.

Selenium is another trace mineral that should be dosed around 55mcg per day. 60 or 70mcg can be taken by pregnant or nursing mothers as well.

As previously stated 400-800mg of ashwagandha is considered safe and has been demonstrated to have no severe adverse health risks in clinical study data.

(SPECIAL SAVINGS) Find the Most Popular Thyroid Health Supplement Right Now

FAQ

Q. What is a thyroid supplement & what should be in it?

A thyroid supplement is any supplement designed to improve the function of the thyroid. The thyroid is an organ in your neck responsible for producing hormones that regulate mood, metabolism, energy levels, & much more.

Most thyroid supplements will contain a number of vitamins & trace minerals. You’ll want it. Thyroid supplement that contains iodine, zinc, selenium, copper, vitamin B, and Vitamin A.

Some thyroid supplements will also add herbal extracts for added support, although they are not necessarily required to see results. Ashwagandha & cayenne pepper are the two most common herbal extracts added in thyroid supplements – along with kelp and turmeric.

Q. Can thyroid supplements replace thyroid prescription medications?

If you’ve been diagnosed with hypothyroidism, you should work with your doctor to find the right medication for your individual needs. Thyroid supplements are in no way a replacement for these prescription medications.

Some medical doctors even caution their use because many thyroid products contain active amounts of thyroid hormones. Unlike prescription medications, these hormone levels are unregulated and may put your thyroid levels out of a healthy range.

If you want to take thyroid medication, speak to your doctor first, and clear it with him or her if you’ve been diagnosed with hypothyroidism.

Q. What vitamins are good for the thyroid?

Thyroid health is a complicated medical issue and a number of factors can cause thyroid issues. With that said, some vitamins & minerals have demonstrated a clear ability to improve thyroid function.

Vitamin B for example has been shown to improve thyroid function. Iodine is essential for the thyroid to synthesize hormones and is therefore essential to thyroid function. Selenium, magnesium, zinc, and copper are all trace minerals that are thought to have an important role in the health of your thyroid.

Q. Can any foods help with thyroid function?

The best foods to ensure your thyroid can function properly are those that provide your body with the exact vitamins and trace minerals we mentioned above.

Iodine-rich foods include oysters, kelp, and fish. Spirulina, mushrooms, almonds, spinach, and broccoli are all great sources of zinc. Eggs, brown rice, and other whole grains are rich in selenium.

In general, a healthy, well-balanced diet is key for proper thyroid function. Avoiding sugary foods, alcohol, and smoking cigarettes, are a few ways you can reduce the risk for poor thyroid function.

Q. What else affects thyroid function?

Several things can impact your thyroid function – both negatively and positively. For example, a poor diet has been linked to impaired thyroid function. Cigarette use, alcohol consumption, and poor sleep habits have also been linked to impaired thyroid function.

Various autoimmune disorders are known to cause thyroid issues. This is because many autoimmune disorders cause the body’s white blood cells to attack the tissues in the body, including the thyroid. This weakens the organs and can negatively impact function.

Medications containing lithium may also impair thyroid function. Medical doctors can typically recommend a different prescription in the event that it causes thyroid issues, but this not always the case.

In general, there are a dozen or more factors that can have a huge role in your thyroid function. Many are out of your control but there are plenty of things you can do to ensure your diet and lifestyle habits aren’t contributing to poor thyroid function.

Eating a well-balanced diet, exercising regularly, & getting a good night’s sleep are three easy ways to put your thyroid in a position to function properly. Limiting tobacco & alcohol use are two more ways as well.

Q. How do thyroid supplements affect weight?

Believe it or not, thyroid supplements can potentially cause you to gain or lose weight. This is depending on how active your thyroid currently is.

If you have a slow thyroid, then you may experience weight loss by taking a thyroid supplement since the thyroid regulates your body’s metabolism. Ashwagandha, a popular herbal extract added to many thyroid supplements, is also said to improve body composition so you may see some added weight loss in products with the herb.

Although uncommon, thyroid products can cause weight gain. However, this is incredibly rare and has only been documented a few times. If for some reason you think you are gaining weight as a result of a thyroid supplement, simply discontinue use and consult your doctor to get his or her opinion on the matter.

Q. How do thyroid supplements differ from prescription thyroid medications?

There are definitive differences between thyroid medications (those that require a prescription from a medical doctor) and over-the-counter thyroid supplements.

Prescription thyroid medications like levothyroxine provide your body with synthetic replacements for thyroid hormones. These hormones are needed to prevent the symptoms of hypothyroidism from occurring.

Thyroid supplements are the exact opposite. Their main function is to provide minerals and vitamins that support your body’s own ability to maintain healthy thyroid functioning.

Sadly, some shady supplement companies have been caught adding thyroid hormones in their supplements. This can cause serious issues for people who take thyroid supplements and can make their thyroid go into overdrive and become too active.

This is why it is important to find a thyroid supplement with zero additives, fillers, or unknown ingredients. Any supplement you try should only contain vitamins, minerals, and herbal extracts. Make sure the supplement is clearly labeled and that you can identify all over the ingredients and the dosage of each ingredient.

Final Thoughts

Thyroid supplements are meant to provide your body with essential vitamins and minerals needed to produce healthy levels of thyroid hormone.

Since the functions of thyroid hormones are included in a wide range, poor thyroid function can cause severe impacts on your health. Poor thyroid function has been linked to depression, weight gain, impaired cognitive ability, and muscle issues.

With the right formulation of vitamins, minerals, and herbal extracts, a thyroid supplement can improve thyroid function, thus reversing these effects and potentially having a significantly positive impact on your health.

Buy the Best Rated, Top Ranked, Most Popular Thyroid Health Supplement for Powerful Support Today

Official Website: https://thyroidfactor.com/

Contact Details: Thyroid Factor

Email: [email protected]

Phone: 1-800-207-4562

About MarketingByKevin.com

This product review is published by Marketing By Kevin. Marketing By Kevin reviews are researched and formulated by a group of experienced natural health advocates with years of dedication and determination to finding the highest quality health products and wellness programs available. It should be noted that any purchase derived from this resource is done at your own peril. It is recommended to consult with a qualified professional healthcare practitioner before making an order today if there are any additional questions or concerns. Any order finalized from this release’s links are subject to the entire terms and conditions of the official website’s offer. The researched information above does not take any direct or indirect responsibility for its accuracy.

Affiliate Disclosure:

The links contained in this product review may result in a small commission to Marketing By Kevin if you opt to purchase the product recommended at no additional cost to you. This goes towards supporting our research and editorial team and please know we only recommend high quality products. 

Disclaimer:

Please understand that any advice or guidelines revealed here are not even remotely a substitute for sound medical advice from a licensed healthcare provider. Make sure to consult with a professional physician before making any purchasing decision if you use medications or have concerns following the review details shared above. Individual results may vary as the statements made regarding these products have not been evaluated by the Food and Drug Administration. The efficacy of these products has not been confirmed by FDA-approved research. These products are not intended to diagnose, treat, cure or prevent any disease.

Product support: [email protected]

Media Contact: [email protected]

Foods to Avoid if You Have Thyroid Issues – Cleveland Clinic
People with thyroid conditions can’t manage their condition through diet. But, eating the wrong foods or taking the wrong supplements can cause trouble.
 Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services.									Policy
Among the foods to go easy on are soy, kelp and dietary supplements like iodine and selenium, says endocrinologist Christian Nasr, MD. “There is a lot of literature on what people shouldn’t do,” he says.
Should people with thyroid problems avoid these foods?
Soy: If you have hypothyroidism, yes. Eating too much soy causes problems only for those with hypothyroidism, which occurs when your thyroid gland does not make enough thyroid hormones, Dr. Nasr says.
The main problem is that soy may hinder absorption of the hormones that such patients take.
“Some studies show that if you eat a lot of soy, or drink a big glass of soy milk, within one hour of taking a thyroid hormone, it might affect absorption,” Dr. Nasr says. “Many individuals depend on a consistent absorption of those hormones to achieve a steady state.”
Generally, experts
 recommend that people who have a borderline thyroid — one that’s a little
 underactive but you’re still trying to preserve thyroid function — do not to
 consume large amounts of soy every day, he adds.
Turnips and root
 vegetables: No. These vegetables are
 sometimes thought to cause thyroid problems, but that’s not the case, Dr. Nasr
 says. They are good for your diet, regardless of any thyroid issues.
One root vegetable that is the exception is cassava, a common staple in certain parts of Africa. This plant “is known to produce toxins that can slow an already underactive thyroid, especially in the presence of an iodine deficiency,” Dr. Nasr says. “But that’s not relevant here in the United States, unless you cook cassava and you eat it every day.”
Kelp: No, but don’t take it in supplement form. People with thyroid issues should not have more than an average daily recommended intake of 158 to 175 micrograms of kelp per day, Dr. Nasr says. The concentration of kelp in foods is generally not enough to cause a problem, but a kelp capsule can contain as much as 500 micrograms, he says. “Those recommendations to go easy on kelp are for people who don’t understand and take three capsules per day. If you eat an average amount of kelp once a day, that’s not a problem.” Pregnant women especially should avoid ingesting large amounts of kelp, as it may put them at risk for developing fetal goiter, he adds.
Cabbage and cruciferous veggies: Yes. Even though they are good for us, cabbage and other cruciferous vegetables eaten raw in large quantities, especially in the context of iodine deficiency or borderline iodine levels, can result in hypothyroidism. These vegetables generate a substance that competes with the uptake of iodine by the thyroid.
Should people with thyroid problems avoid these supplements?
Iodine: Yes. Avoid it as a supplement whether you have
 hyperthyroidism or hypothyroidism. The effect of iodine supplements can vary by
 person, causing the thyroid to produce either too much or too little hormone.
Certain alternative
 medicine websites or doctors tell patients that iodine is good for your
 thyroid, Dr. Nasr says, but “if there is anybody who shouldn’t take iodine, it
 is thyroid patients.” Such claims are
 made because iodine deficiency is the No. 1 cause of thyroid conditions
 in the world, he says. But that’s not true in the U.S., where we have iodine in
 our diets. Iodine is added to many foods, and not just salt, he says.
However, Dr. Nasr says that people on restrictive diets may consider adding a daily multivitamin that contains the recommended daily allowance of iodine.
He also assures patients
 not to worry that you are getting too much iodine from everyday foods. “You would
 have to eat a ton of it to cause problems,” he says. “It’s not, ‘don’t eat
 anything with iodine.’ It’s, ‘don’t eat a bunch of iodine.’ And patients should
 be careful with iodine-concentrated supplements.”
Selenium: No, but don’t take more than 200 micrograms per day.
 Selenium, which is needed to support efficient thyroid function, is not
 something you would typically find at the grocery store, but an alternative
 medicine doctor might prescribe it, Dr. Nasr says. You can also get it in foods
 like fish, Brazil nuts, meat and poultry. A selenium supplement is OK to use
 “as long as you’re not overdoing it,” he says.
Supplements For Thyroid Health: 10 Natural Options
Dietary supplements for thyroid health can address underlying nutrient deficiencies, stress, and hormonal imbalances, all of which can be root causes of a thyroid disorder.
Approaching hypothyroidism with supplements, in addition to lifestyle changes, can often help people to avoid the need for medications in the future.
We’ll talk about diagnosing the different root causes of thyroid disorders later in this article. Or you can check out this post about diagnosing primary hypothyroidism. Spoiler: Our blood tests measure more than just TSH thyroid hormone levels to determine if you have a healthy thyroid.
Note: It’s critical not to confuse hypothyroidism and hyperthyroidism. Hypothyroidism describes an underactive thyroid. Hyperthyroidism is when your thyroid is overactive. Each condition features different symptoms, but both can be caused by different autoimmune issues. 
In this article, we’ll clarify which condition each supplement is known to address. In some cases, it’s both!
If you’re struggling with hypothyroidism, schedule a free phone consultation with us. Our patients prove that, often, hypothyroidism can be permanently reversed.
Natural vs. Synthetic Treatments
There are both natural and synthetic options to balance the thyroid. We typically recommend natural thyroid supplements as part of an integrative approach to health, rather than starting with prescription medications.
The term “synthetic thyroid treatments” typically refers to levothyroxine — synthesized T4 that looks and acts like the T4 made in your thyroid gland. To avoid confusion, know that levothyroxine is a thyroid medication, though some incorrectly call it a “synthetic thyroid supplement. ”
What is the difference between natural and synthetic thyroid treatments? Synthetic thyroid treatments (medications) are man-made and must be prescribed by a doctor. Natural supplements are found in nature and may be taken without the advice of a physician (though we recommend talking to your healthcare provider before starting any new supplements).
Natural Thyroid Treatments
How can I boost my thyroid naturally? You can boost your thyroid naturally by reducing stress, reducing allergens and toxins from your daily life, and taking science-backed supplements targeted at the underlying cause(s) for your specific case of thyroid dysfunction.
Natural thyroid supplements are not perfect. Many dietary supplements that are marketed to naturally boost thyroid health actually contain thyroid hormones (T3 and T4) without listing them as ingredients. It’s important to know what’s in your supplements!
It’s also common for patients to “DIY” their own “natural thyroid treatments” by choosing supplements they think will work for their condition. However, this can be dangerous. 
As a functionally minded healthcare provider, I only recommend supplements to patients based on their individual needs, deficiencies, and other factors.
10 Natural Thyroid Supplements
The top 10 natural thyroid supplements that may help your symptoms include:
Vitamin D
Selenium
Iodine
Zinc
Probiotics
DIM
Glutathione
Green tea extract
Curcumin
Ashwagandha
It is critical to consider the root cause and type of thyroid condition before taking any supplements. We recommend speaking to your doctor or contacting us to create the best plan for your individual health.
What are some pros of taking thyroid supplements? The pros of taking thyroid supplements include science-backed benefits that can treat the underlying cause of your thyroid disorder. Natural thyroid supplements typically boast lesser side effects than medications.
Check out these research-based supplements for various root causes of abnormal thyroid function.
Vitamin D
Vitamin D is a hormone your body naturally produces. However, a large portion of the population is deficient in vitamin D, due in part to our indoor lifestyles. This vitamin deficiency may lead to an underactive thyroid.
Traditionally, scientists believed that vitamin D was mainly linked to autoimmune thyroiditis, but a 2020 study found that even non-autoimmune hypothyroidism was associated with vitamin D deficiency.
This 2018 study shows that Hashimoto’s thyroiditis and vitamin D deficiency are inextricably linked.
A randomized, double-blind, placebo-controlled trial showed that vitamin D improved TSH levels and calcium levels in hypothyroid patients. Multivitamins including vitamin D may also be a good idea. 
For medical-grade, 3rd-party tested Vitamin D, check out our Prime D + K.
Selenium
“In the 1990s, selenium was identified as a component of an enzyme that activates thyroid hormone,” says a 2020 study published in Nature Reviews Endocrinology. Since then, selenium deficiency has been studied as a common cause of thyroid disorders.
Selenium seems to be an excellent answer to both Graves’ disease (autoimmune hyperthyroidism) and Hashimoto’s disease (autoimmune hypothyroidism).
It may help fight postpartum thyroiditis, which occurs when new mothers experience abnormal thyroid function.
Iodine
Moderate amounts of iodine supplements can help prevent autoimmune diseases like Hashimoto’s and Graves’ — and may reduce symptoms of hypothyroidism.
Your body cannot produce iodine on its own, so it depends on dietary iodine to produce and secrete thyroid hormones, T3 and T4. Iodized salt is just salt fortified with iodine — a large-scale effort to reduce goiters in the American population that began in 1924.
Iodine shows promise for treating hyperthyroidism as well. In cases of Graves’ disease, when patients cannot take antithyroid medications due to side effects, potassium iodide has been used to control thyroid activity successfully. Iodine can acutely inhibit hormonal secretion.
Radioactive iodine is a treatment for hyperthyroidism that is gaining popularity. However, radioactive iodine is very different from iodine supplements — talk to specialists to find out more about this treatment option.
Iodine deficiency is also a leading cause of goiters, a thyroid disorder. Iodine is a standard treatment for goiters.
Be warned, though. Even if iodine is a common treatment for thyroid disorders, too much iodine can trigger thyroid problems. This should be taken with medical supervision.
Zinc
Zinc is an essential mineral in the production of thyroid hormones T3, T4, and TSH. A zinc deficiency can lead to hypothyroidism or hyperthyroidism. If you are low on zinc, a zinc supplement could help to treat your thyroid disorder.
It’s worth noting that zinc deficiency could be a symptom or a cause of hypothyroidism. It works both ways, complicating the diagnostic process.
Zinc is often paired with magnesium, selenium, or even copper for optimal results. However, we recommend only taking mineral supplements you know that you are deficient in, so please seek out testing through your healthcare provider. 
At PrimeHealth, testing for these nutrients is standard, as they play such a huge role in health, especially of the thyroid. 
For medical-grade, 3rd-party tested Zinc, check out Prime Zinc.
Probiotics
Leaky gut syndrome is a common root cause of hypothyroidism. Probiotics are a common and proven treatment for leaky gut, also known as intestinal permeability.
Probiotics treat leaky gut, which is a significant risk factor for Hashimoto’s hypothyroidism. If an endocrinologist or other healthcare professional believes that you may have leaky gut syndrome, probiotics can be a great supplement to add.
Be careful about using probiotics if you have SIBO. This means that intestinal bacteria linger in the small intestine, causing an overgrowth, and adding probiotics could potentially make this situation worse. Probiotics provide full benefit when they occupy your large intestine, not your small intestine.
DIM
Diindolylmethane (DIM) is a supplement typically used to treat female hormone imbalance, most notably estrogen dominance. DIM can aid female patients suffering from hormone-related thyroid problems.
Other studies show that DIM has regulated hormone levels in women with various conditions.
We also often recommend chasteberry for women with hormonal imbalance.
Glutathione
Glutathione fights oxidative stress that may increase the severity of hypothyroidism if left unchecked. Glutathione is a superb antioxidant. If inflammation is triggering your autoimmunity, glutathione is a great supplement.
A deficiency of glutathione can lead to hypothyroidism. Whether you’re deficient or not, glutathione may improve your thyroid health.
N-acetylcysteine is a precursor to glutathione. As a supplement, N-acetylcysteine can also help fight inflammation and free radicals.
Green Tea
Green tea contains a catechin called epigallocatechin-3-gallate (EGCG). EGCG is a powerful antioxidant that benefits you in similar ways to glutathione.
This 2018 study shows how EGCG protects against autoimmune thyroid disorders via its anti-inflammatory properties.
Because green tea contains caffeine, there are potential side effects like insomnia if you consume caffeine too late in the day.
Curcumin
Curcumin is a powerful antioxidant known for its anti-inflammatory properties that helps treat osteoarthritis. However, curcumin’s anti-inflammatory properties may also fight against autoimmune diseases, like Hashimoto’s.
Taking curcumin with other anti-inflammatory compounds could help reduce the size of thyroid nodules, which are symptoms of hypothyroidism.
Turmeric in the diet should help increase your curcumin intake. However, it’s worth mentioning that the bioavailability of curcumin in turmeric is very low — meaning your body doesn’t absorb much curcumin. Your digestive tract destroys most of the curcumin in turmeric.
Liposomal curcumin is a novel approach to solving the bioavailability problem. Liposomes deliver curcumin (or whatever is contained within) directly to your cells, cleverly avoiding destruction in your digestive tract by mimicking a natural cell wall.
Ashwagandha
Ashwagandha is a common treatment in ancient Ayurvedic medicine. Studies show that ashwagandha is an effective treatment for hypothyroidism. 
Ashwagandha is considered an adaptogenic herb, which helps the adrenal glands adapt to the stress that you are experiencing. Since the adrenal glands and thyroid are so intricately connected, it’s no surprise that supplements that nourish the adrenals can also help support thyroid function.
Science reveals that ashwagandha offers a lot of thyroid support and can help fight and prevent thyroid disease.
Supplements For Underlying Issues
In order to take the right supplements for thyroid problems, you need to know what underlying issues are triggering your thyroid condition.
When should you take thyroid supplements? You should take thyroid supplements when lifestyle and dietary changes haven’t led to the healing you were hoping for.
Let a qualified healthcare provider diagnose the root cause of your thyroid condition, and have a conversation with the healthcare expert about whether a supplement is suitable for your situation.
Below, supplements are broken down by which root cause of thyroid disorder they treat.
Hashimoto’s Disease
Also called Hashimoto’s thyroiditis or autoimmune thyroiditis, Hashimoto’s disease is an autoimmune disorder that leads to hypothyroidism, which can cause weight gain, fatigue, cold sensitivity, and constipation.
It has many potential root causes, so it is essential to diagnose the underlying cause(s) before treatment or supplementation.
The most common causes of Hashimoto’s disease (and the supplements to address each) are:
Hormone imbalance — If any of your hormone levels are imbalanced, this may trigger Hashimoto’s disease. The best supplements for hormone imbalance are chasteberry and DIM.
Leaky gut — When your intestines are chronically inflamed, your intestines might allow toxins to escape from the gut into the bloodstream. Leaky gut is both a cause and a symptom of hypothyroidism. The best supplements for leaky gut are probiotics, zinc, and curcumin. To heal your gut with the help of a PrimeHealth expert, join our online Prime Gut Health course.
Infections — Tick-borne infections (like Lyme disease), viral infections (like Epstein-Barr), or gut infections like SIBO, may cause Hashimoto’s thyroiditis. Some of the best supplements for infections are vitamins C and D, zinc, and green tea extract.
Toxin exposure — Harmful toxins can mess with your body, particularly your thyroid gland. Watch out for heavy metal exposure, mold toxins, and industrial chemicals. Supplements to help fight toxin exposure include glutathione, milk thistle, and zinc.
Nutrient deficiency — Nutrient deficiencies could lead to Hashimoto’s. Dietary supplementation can treat these deficiencies. The most commonly seen deficiencies include vitamin D, zinc, iron,  selenium, and iodine. Other (less common) deficiencies to look for are in vitamin B12, folate, and L-tyrosine, an amino acid.
Graves’ Disease
Graves’ disease is an autoimmune disorder that triggers an overactive thyroid, or  hyperthyroidism, which can lead to weight loss, anxiety, insomnia, heat sensitivity, and diarrhea.
Like Hashimoto’s, you need to know the underlying cause of your Graves’ disease before treatment or supplementation.
Common hyperthyroidism supplements and Graves’ disease supplements include:
Risks Of Thyroid Supplements
What are the side effects of thyroid supplements? Though rare, many natural thyroid supplements do have side effects. Always speak with your healthcare provider about which supplements you should stop or initiate during pregnancy, as this changes your needs.
Too much vitamin D can lead to hypercalcemia, stomach discomfort, kidney injury, and bone loss. But we’re talking a lot of vitamin D. Most people do best to take around 5,000 IU of vitamin D3 daily.
Severe selenium side effects may include metallic taste, tenderness, fatigue, hair loss, and nausea. These indicate serious problems, and you should consult a doctor if any of these side effects occur.
Iodine supplementation may lead to overconsumption of iodine, which could cause nausea and stomach pain. Too much iodine can lead to worsening thyroid illness.
Too much zinc can cause heavy metal toxicity, nausea, diarrhea, metallic taste, kidney problems, and stomach damage.
Probiotics aren’t the best option for patients with SIBO. Probiotics’ side effects include digestive distress and flatulence.
DIM may trigger side effects, such as headache, nausea, and diarrhea.
Glutathione doesn’t have many potential side effects, but long-term glutathione supplementation has been linked with zinc deficiency. You may consider combining zinc with glutathione supplements.
Green tea extract can cause insomnia, increased heart rate, and nervousness because of its caffeine content. Excessive doses of EGCG could lead to liver or kidney problems, as well as low blood sugar.
Curcumin can cause digestive distress, even at relatively low levels. This is common, but uncomfortable. Your stool may also turn yellow.
Nutrition For Thyroid Health
Of course, eating healthier can improve your overall wellness, possibly even your thyroid conditions. Food allergens and toxins can trigger Hashimoto’s hypothyroidism.
If you can fix your condition with dietary changes, you don’t really need dietary supplements.
A healthy diet can eliminate toxins, lessen inflammation, and regulate hormones to help with thyroid issues. Our guide to a hypothyroidism diet can help you get started!
Some experts (us included) suggest the Autoimmune Paleo (AIP) diet for 3-6 months to eliminate and identify potential inflammatory triggers from your diet. If your thyroid disorder improves, we know it was due to food triggers.
Once your condition improves, we will slowly reintroduce foods into your diet. If your condition worsens after adding a certain food, we will re-eliminate the food from your diet.
Pregnant women should not adhere to the Autoimmune Paleo diet. 
Key Takeaways
Reversing your hypothyroidism depends on many factors, including lifestyle changes, dietary adjustments, and stress reduction. As part of these changes, supplements like iodine or vitamin D can play a part in your journey to hypothyroidism healing.
We don’t believe prescription medications should be the first response to thyroid disease. Natural options can produce excellent results by addressing the root cause of your illness.
If you’re interested in hypothyroidism supplements, check out our online store. Or, if you want to talk to a medical professional to see how we can help, schedule your free phone consultation right away.
Sources
Kang, G. Y., Parks, J. R., Fileta, B., Chang, A., Abdel-Rahim, M. M., Burch, H. B., & Bernet, V. J. (2013). Thyroxine and triiodothyronine content in commercially available thyroid health supplements. Thyroid, 23(10), 1233-1237.
Ahi, S., Dehdar, M. R., & Hatami, N. (2020). Vitamin D deficiency in non-autoimmune hypothyroidism: a case-control study. BMC endocrine disorders, 20(1), 1-6.
Botelho, I. M. B., Neto, A. M., Silva, C. A., Tambascia, M. A., Alegre, S. M., & Zantut-Wittmann, D. E. (2018). Vitamin D in Hashimoto’s thyroiditis and its relationship with thyroid function and inflammatory status. Endocrine journal, 65(10), 1029-1037.
Talaei, A., Ghorbani, F., & Asemi, Z. (2018). The effects of Vitamin D supplementation on thyroid function in hypothyroid patients: A randomized, double-blind, placebo-controlled trial. Indian journal of endocrinology and metabolism, 22(5), 584.
Winther, K. H., Rayman, M. P., Bonnema, S. J., & Hegedüs, L. (2020). Selenium in thyroid disorders—essential knowledge for clinicians. Nature Reviews Endocrinology, 16(3), 165-176.
Zheng, H., Wei, J., Wang, L., Wang, Q., Zhao, J., Chen, S., & Wei, F. (2018). Effects of selenium supplementation on Graves’ disease: a systematic review and meta-analysis. Evidence-Based Complementary and Alternative Medicine, 2018.
Toulis, K. A., Anastasilakis, A. D., Tzellos, T. G., Goulis, D. G., & Kouvelas, D. (2010). Selenium supplementation in the treatment of Hashimoto’s thyroiditis: a systematic review and a meta-analysis. Thyroid, 20(10), 1163-1173.
Santos, L. R., Neves, C., Melo, M., & Soares, P. (2018). Selenium and selenoproteins in immune mediated thyroid disorders. Diagnostics, 8(4), 70.
Duntas, L. H. (2015). The role of iodine and selenium in autoimmune thyroiditis. Hormone and Metabolic Research, 47(10), 721-726.
Okamura, K., Sato, K., Fujikawa, M., Bandai, S., Ikenoue, H., & Kitazono, T. (2014). Remission after potassium iodide therapy in patients with Graves’ hyperthyroidism exhibiting thionamide-associated side effects. The Journal of Clinical Endocrinology & Metabolism, 99(11), 3995-4002.
Emerson, C.H.., Anderson, A.J., Howard, W.J., & Utiger, R.D.. (1975). Serum thyroxine and triiodothyronine concentrations during iodide treatment of hyperthyroidism. The Journal of Clinical Endocrinology & Metabolism, 40(1), 33-36.
Chung, H. R. (2014). Iodine and thyroid function. Annals of pediatric endocrinology & metabolism, 19(1), 8.
Betsy, A., Binitha, M. P., & Sarita, S. (2013). Zinc deficiency associated with hypothyroidism: an overlooked cause of severe alopecia. International journal of trichology, 5(1), 40.
Severo, J. S., Morais, J. B. S., de Freitas, T. E. C., Andrade, A. L. P., Feitosa, M. M., Fontenelle, L. C., … & do Nascimento Marreiro, D. (2019). The role of zinc in thyroid hormones metabolism. International Journal for Vitamin and Nutrition Research.
Krishna Rao, R., & Samak, G. (2013). Protection and restitution of gut barrier by probiotics: nutritional and clinical implications. Current Nutrition & Food Science, 9(2), 99-107.
Mu, Q., Kirby, J., Reilly, C. M., & Luo, X. M. (2017). Leaky gut as a danger signal for autoimmune diseases. Frontiers in immunology, 8, 598.
Rajoria, S., Suriano, R., Parmar, P. S., Wilson, Y. L., Megwalu, U., Moscatello, A., … & Tiwari, R. K. (2011). 3, 3′-Diindolylmethane modulates estrogen metabolism in patients with thyroid proliferative disease: a pilot study. Thyroid, 21(3), 299-304.
Alois, M., & Estores, I. M. (2019). Hormonal Regulation In Pcos Using Acupuncture And Herbal Supplements: A Case Report And Review Of The Literature. Integrative Medicine: A Clinician’s Journal, 18(5), 36.
Roemheld-Hamm, B. (2005). Chasteberry. American family physician, 72(5), 821-824.
Silvagno, F., Vernone, A., & Pescarmona, G. P. (2020). The role of glutathione in protecting against the severe inflammatory response triggered by COVID-19. Antioxidants, 9(7), 624.
Chakrabarti, S. K., Ghosh, S., Banerjee, S., Mukherjee, S., & Chowdhury, S. (2016). Oxidative stress in hypothyroid patients and the role of antioxidant supplementation. Indian journal of endocrinology and metabolism, 20(5), 674.
Moustafa, S. A. (2001). Effect of glutathione (GSH) depletion on the serum levels of triiodothyronine (T3), thyroxine (T4), and T3/T4 ratio in allyl alcohol-treated male rats and possible protection with zinc. International journal of toxicology, 20(1), 15-20.
Li, J. (2018). Neuroprotective effect of (‑)‑epigallocatechin‑3‑gallate on autoimmune thyroiditis in a rat model by an anti‑inflammation effect, anti‑apoptosis and inhibition of TRAIL signaling pathway. Experimental and therapeutic medicine, 15(1), 1087-1092.
Menon, V. P., & Sudheer, A. R. (2007). Antioxidant and anti-inflammatory properties of curcumin. The molecular targets and therapeutic uses of curcumin in health and disease, 105-125.
Stancioiu, F., Mihai, D., Papadakis, G. Z., Tsatsakis, A., Spandidos, D. A., & Badiu, C. (2019). Treatment for benign thyroid nodules with a combination of natural extracts. Molecular medicine reports, 20(3), 2332-2338.
Marton, L. T., Barbalho, S. M., Sloan, K. P., Sloan, L. A., Goulart, R. D. A., Araújo, A. C., & Bechara, M. D. (2020). Curcumin, autoimmune and inflammatory diseases: Going beyond conventional therapy–A systematic review. Critical Reviews in Food Science and Nutrition, 1-19.
Sharma, A. K., Basu, I., & Singh, S. (2018). Efficacy and safety of ashwagandha root extract in subclinical hypothyroid patients: a double-blind, randomized placebo-controlled trial. The Journal of Alternative and Complementary Medicine, 24(3), 243-248.
Gannon, J. M., Forrest, P. E., & Chengappa, K. R. (2014). Subtle changes in thyroid indices during a placebo-controlled study of an extract of Withania somnifera in persons with bipolar disorder. Journal of Ayurveda and integrative medicine, 5(4), 241.
Kapil, U. (2007). Health consequences of iodine deficiency. Sultan Qaboos University Medical Journal, 7(3), 267.
Nordio, M. (2017). A novel treatment for subclinical hyperthyroidism: a pilot study on the beneficial effects of l-carnitine and selenium. Eur Rev Med Pharmacol Sci, 21(9), 2268-2273.
Kaplan, D., & Dosiou, C. (2021). Two Cases of Graves’ Hyperthyroidism Treated With Homeopathic Remedies Containing Herbal Extracts from Lycopus spp. and Melissa officinalis. Journal of the Endocrine Society, 5(Supplement_1), A971-A971.
Azezli, A. D., Bayraktaroglu, T., & Orhan, Y. (2007). The use of konjac glucomannan to lower serum thyroid hormones in hyperthyroidism. Journal of the American College of Nutrition, 26(6), 663-668.
‘Thyroid Support’ Supplements May Be Risky
Oct. 28, 2011 – Nine out of 10 “thyroid support” pills tested by Mayo Clinic researchers contain “risky” levels of thyroid hormones.
A wide range of supplements that claim to support or improve thyroid function are available online and in retail stores. Some list only herbs as ingredients. Others are capsules filled with dried, ground-up thyroid gland from pigs or cows.
People take the supplements because they may feel tired, or for unexplained weight gain — symptoms they interpret as a sign their bodies are making too little thyroid hormone.
When a number of his patients told him they were taking the supplements, endocrinologist Victor Bernet, MD, of the Mayo Clinic, Jacksonville, Fla., became curious. Might they contain the same thyroid hormone as Levothroid, Levoxyl, Synthroid, Unithroid and other prescription drugs used to treat thyroid hormone deficiency?
Yes, Bernet says – and it’s risky. “Even a little too much T4 can give a person palpitations, could give atrial fib and blood pressure issues and such,” he tells WebMD. “We have people coming in feeling nervous, can’t sleep, decreased exercise tolerance, hearts running overtime.”
T4 (thyroxine) is the active ingredient in Synthroid and other prescription drugs used to treat thyroid deficiency.
Bernet and colleagues tested 10 different supplements, selected because they appeared to be the most popular products sold for “thyroid support.” Five of the products listed animal thyroid gland as an ingredient, five did not.
The result: nine of the 10 pills contained T4. At the dose recommended on the label, four of the pills delivered T4 at doses ranging from 8.6 to 91.6 micrograms per day. A typical daily dose of prescription T4 is 50 to 150 daily micrograms, Bernet says.
Nine of the supplements carried another thyroid hormone, triiodothyronine, or T3. Five delivered daily T3 doses of more than 10 micrograms per day. “That’s more than half of what the body would normally make in a day,” Bernet says.
“Thyroid hormones are medications that should be bought only under prescription,” Bernet tells WebMD. “I do not recommend anyone take any of these supplements. … This is a general warning to patients that 90% of those products we randomly picked have clinically significant amounts of thyroid hormone.”
Thyroid Support Supplements Legal
The supplements are legal as long as they aren’t spiked with pharmaceutical drugs, according to federal law. That law, passed in 1994, permits the sale of “a dietary substance for use by man to supplement the diet by increasing the total dietary intake (e.g., enzymes or tissues from organs or gland).”
Firms that sell the supplements are responsible for “determining” that their products are safe and that claims made about them “are substantiated by adequate evidence to show they are not false or misleading.” But the law exempts these supplements from having to be approved by the FDA.
“Thyroid support supplements have been around for a long time,” Duffy MacKay, ND, vice president for scientific and regulatory affairs for the Council for Responsible Nutrition (CRN), tells WebMD. CRN is the trade group that represents the supplement industry.
“The presence of desiccated glands in dietary supplements is perfectly legal,” MacKay says. “The amounts of hormone in the product should reflect what naturally occurs in the [animal] gland itself. … These are not extremely high levels of thyroid hormone.”
But MacKay says his comments are limited to firms “following the rules.” He condemns “spiked products masquerading as supplements.”
The FDA did not respond to WebMD’s request for comment on the Bernet study findings.
Bernet says thyroid support products should be more tightly regulated. MacKay says Bernet is entitled to his opinion, but that if he wants things changed he should write to his congressman to seek a change in federal law.
However, MacKay and Bernet fully agree on at least one major point: Anyone thinking of taking a thyroid support supplement should talk with a medical professional, and should be sure to tell all of their doctors what they are taking.
Bernet reported the study findings in a presentation to the annual meeting of the American Thyroid Association, held Oct. 26-30 in Indian Wells, Calif.
Health Benefits beyond Basic Nutrition
Nutrients. 2019 Sep; 11(9): 2214.
Salvatore Benvenga
1Department of Clinical and Experimental Medicine-Endocrinology, University of Messina, via Consolare Valeria-Gazzi, 98125 Messina, Italy; [email protected]
2Master Program on Childhood, Adolescent and Women’s Endocrine Health, University of Messina, via Consolare Valeria-Gazzi, 98125 Messina, Italy
3Interdepartmental Program on Molecular and Clinical Endocrinology and Women’s Endocrine Health, AOU Policlinico G. Martino, via Consolare Valeria-Gazzi, 98125 Messina, Italy
Ulla Feldt-Rasmussen
4Medical Endocrinology and Metabolism PE 2132, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark; kd.hr@tdlefu
Daniela Bonofiglio
5Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende (CS), Italy; [email protected]
Ernest Asamoah
6Community Physicians Network, Diabetes & Endocrinology Care, 8435 Clearvista Place, Suite 101, Indianapolis, IN 46256, USA
1Department of Clinical and Experimental Medicine-Endocrinology, University of Messina, via Consolare Valeria-Gazzi, 98125 Messina, Italy; [email protected]
2Master Program on Childhood, Adolescent and Women’s Endocrine Health, University of Messina, via Consolare Valeria-Gazzi, 98125 Messina, Italy
3Interdepartmental Program on Molecular and Clinical Endocrinology and Women’s Endocrine Health, AOU Policlinico G. Martino, via Consolare Valeria-Gazzi, 98125 Messina, Italy
4Medical Endocrinology and Metabolism PE 2132, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark; kd.hr@tdlefu5Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Arcavacata di Rende (CS), Italy; [email protected]
6Community Physicians Network, Diabetes & Endocrinology Care, 8435 Clearvista Place, Suite 101, Indianapolis, IN 46256, USA
Received 2019 Jul 29; Accepted 2019 Sep 9.
Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).This article has been cited by other articles in PMC.
Abstract
In recent years, there has been a growing interest in nutraceuticals, which may be considered as an efficient, preventive, and therapeutic tool in facing different pathological conditions, including thyroid diseases. Although iodine remains the major nutrient required for the functioning of the thyroid gland, other dietary components play important roles in clinical thyroidology—these include selenium, l-carnitine, myo-inositol, melatonin, and resveratrol—some of which have antioxidant properties. The main concern regarding the appropriate and effective use of nutraceuticals in prevention and treatment is due to the lack of clinical data supporting their efficacy. Another limitation is the discrepancy between the concentration claimed by the label and the real concentration. This paper provides a detailed critical review on the health benefits, beyond basic nutrition, of some popular nutraceutical supplements, with a special focus on their effects on thyroid pathophysiology and aims to distinguish between the truths and myths surrounding the clinical use of such nutraceuticals.
Keywords: nutraceuticals, thyroid function, dietary supplements
1. Introduction
1.1. Definition of Nutraceutical
The definition of nutraceuticals is still in the grey area between food, food supplements, and pharmaceuticals. Some definitions [1,2,3,4,5] of nutraceuticals are provided in . The term “nutraceutical” was coined in 1989 by Stephen De Felice, founder and chairman of the Foundation for Innovation in Medicine, an American organization which encourages medical health research. He defined a nutraceutical as a “food, or parts of a food, that provide medical or health benefits, including the prevention and treatment of disease” [4]. Japan was among the first countries to face the issue of regulating food supplements and foodstuffs. This legislation, originally set in 1991, evolved into the 2003 Health Promotion Law [5]. The current European regulation (Regulation No. 1924/2006 of the European Parliament and of the Council, recently updated by EU Regulation 2015/2283) defines food categories and includes a definition of food supplements, although there is no official mention or recognition the term “nutraceutical” [6]. Accordingly, the European Food Safety Authority (EFSA) does not make any distinction between “food supplements” and “nutraceuticals” for beneficial health claim applications for new products. In a similar way, the Dietary Supplement Health and Education Act (DSHEA, 1994) [7] defined dietary supplements as a category of food, as did the US Food and Drug Administration (FDA) [8]. Indeed, in America “medical foods” and “dietary supplements” are regulatory terms, however “nutraceuticals”, “functional foods”, and other such terms are determined by consultants and marketers, based on consumer trends. Further information on the dietary supplements given by the Food and Drug Administration (FDA) on its website [9] is summarized in Appendix .
Table 1
Some definitions of “nutraceutical”.
Reference
Definition
[1]
“A foodstuff (such as a fortified food or dietary supplement) that provides health benefits in addition to its basic nutritional value. (First known use: 1990)”.
[2]
“A food to which vitamins, minerals, or drugs have been added to make it healthier.”
[3]
“Nutraceuticals, which have also been called medical foods, designer foods, phytochemicals, functional foods and nutritional supplements, include such everyday products as “bio” yoghurts and fortified breakfast cereals, as well as vitamins, herbal remedies and even genetically modified foods and supplements. Many different terms and definitions are used in different countries, which can result in confusion.”
[4]
“I propose to redefine functional foods and nutraceuticals. When food is being cooked or prepared using “scientific intelligence” with or without knowledge of how or why it is being used, the food is called ‘functional food’. Thus, functional food provides the body with the required amount of vitamins, fats, proteins, carbohydrates, etc., needed for its healthy survival. When functional food aids in the prevention and/or treatment of disease(s) and/or disorder(s) other than anemia, it is called a nutraceutical.”
[5]
Nutraceutical combines two words the term ‘nutrition/nutrients’ (a nourishing food component) and ‘pharmaceutical’ (medicine or a substance used as a medication) applied to food or food component products sometimes with active principle from plants that can provide health and medical benefits, including the prevention and treatment of disease.
1.2. Search of the Literature
A PubMed search, run on 14 July 2017, using the word “nutraceutical” as the entry, yielded 67,344 results. Results fell to 4820 using the entry “nutraceuticals AND hormones” and to 553 using the entry “nutraceuticals AND thyroid”. Approximately 18 months later (5 February 2019), the corresponding numbers were 78,919 (+17%), 5538 (+15%) and 642 (+16%), indicating that the interest in the thyroid proceeds with the same pace as that for nutraceuticals in general and hormones in general. Confirmation of these data came from a final search that was run on 9 July 2019 ().
Table 2
Summary of number of articles on given nutraceuticals retrievable on PubMed as of 9 July 2019.
Entry
No. of Items
Proportions
Total
Human
Human/Total
Thyroid/Total
Thyroid/Human
1
nutraceuticals
81,422
52,406
64.4%
N/A
N/A
2
nutraceuticals AND hormones
5698
3664
61.4%
N/A
N/A
3
nutraceuticals AND thyroid
656
487
74.2%
0.8%
0.9%
4
carnitine
16,737
7831
46.8%
N/A
N/A
5
carnitine AND thyroid
145
68
46.9%
0.9%
0.9%
6
inositol
44,801
16,700
37.3%
N/A
N/A
7
inositol AND thyroid
295
141
47.8%
0.6%
0.8%
8
melatonin
24,921
10,740
43.1%
N/A
N/A
9
melatonin AND thyroid
514
195
37.9%
2.1%
1.8%
10
resveratrol
11,983
5447
45.4%
N/A
N/A
11
resveratrol AND thyroid
78
47
60.2%
0.6%
0.9%
12
selenium
33,980
13,333
39.2%
N/A
N/A
13
selenium AND thyroid
938
576
61.4%
2.8%
4.3%
In the following text, different nutraceuticals possibly influencing human thyroid function and/or immunity will be reviewed and commented upon.
A general effect of the nutraceuticals beyond the thyroid effect is not within the scope of this review, nor is a meticulous review of animal or other experimental studies. We were guided by our clinical practices, particularly those for which patients were most curious. As mentioned in the following section, there is indeed a growing market for such nutraceuticals.
There was relatively scant literature on the topic, and most research focused on thyroid cancer and was experimental in nature, concerning the nutraceuticals illustratively mentioned by the Food and Drug Administration, as shown in Appendix .
1.3. Market and Sales
Based on data from a decade ago, annual supplement sales were $23 billion, and about 40,000 supplement products were on the market in the United States [10].l-carnitinel-carnitine market is expected to be worth USD 127 million by 2017, with the United States being the largest market, and the Asia-Pacific region, particularly China, expected to experience a 5.5% annual growth rate through 2017 [12].
No. of items on sale-Amazon: 53; Walgreens: No match; CVS Pharmacy:13.Myo-inositolIn the consumption market, the global consumption value of inositol increases with the 2.01% average growth rate. Europe and China are the mainly consumption regions [11]. With myo-inositol being the most common form of inositols, over the next five years the inositol market, will register a 6.8% compound annual growth rate in terms of revenue, the global market size will reach US $140 million by 2024, from US $94 million in 2019 [13].
No. of items on sale-Amazon: 3; Walgreens: No match; CVS Pharmacy: No match.MelatoninThe North America region is the largest supplier of melatonin, with a production market share nearly 54% in 2016, Europe coming next with 27% [14]. The global market size will reach US $2080 million by 2024, from US $700 million in 2019 [14].
No. of items on sale-Amazon: 122; Walgreens: 11; CVS Pharmacy: 91.ResveratrolResveratrol supplements, with annual sales of $30 million in the United States [15] 
No. of items on sale-Amazon: 45; Walgreens: No match; CVS Pharmacy: 19.SeleniumSelenium market reached $87 million U.S. in 2017 [16].
No. of items on sale-Amazon: 91; Walgreens: No match; CVS Pharmacy: 84.
1.4. The Issue of Purity
“The biggest problem with supplements is that many of them do not actually contain what the label claims. As many as 70% of the supplements on the market either don’t have ingredients that match their labels or contain contaminants of some kind” [17]. In his review, Lockwood aimed to investigate the extent of substandard formulated and raw material nutraceuticals [17]. The key findings were that “published evaluations of over 70 formulations of 25 different nutraceuticals revealed variable quality; no nutraceutical showed consistent high quality, but a number revealed consistent low quality, thereby making the case for closer regulation of manufacturers. Whole food sources have also been shown to be widely variable in constituent levels.” [17]. Concerning the issue of purity, the illegal presence of thyroid hormones in the majority of dietary health supplements marketed for “thyroid support” potentially exposes patients to the risk of developing iatrogenic thyrotoxicosis [18].
In the following text, we now give some data concerning the nutraceuticals dealt upon in our paper. Concerning carnitine, of 12 over-the-counter carnitine formulations, the actual mean content was only 52% of that indicated on the label [19]. Furthermore, of the same 12 preparations, five had unsatisfactory pharmaceutical dissolution characteristics.
Concerning myo-inositol, one study evaluated label accuracy of four myo-inositol products, designed for polycystic ovary syndrome (PCOS) treatment and available on the Italian market, and performed a cost comparison based on myo-inositol content in milligrams for products analyzed [20]. A significant difference in the myo-inositol content, compared with the labeling was found for the products. Only one product contained more than 95% of the myo-inositol content claimed on the label, and there was a product with less than 75% of the labeling amount. Based on a 2-g myo-inositol per day dose, the cost of a 30-day supply ranged from Euro 20.77 and Euro 71.86, after correction by the actual amount of myo-inositol.
One recent study aimed to determine the dose of melatonin in food supplements marketed in Europe (pharmacies of Spain) and the United States (supermarkets of San Francisco, CA, USA) by validating a liquid chromatography method with diode array detection (LC-DAD) [21]. The authors tentatively identified eight tryptophan-related contaminants in melatonin supplements, with only one supplement declaring its addition on the label. Label melatonin doses varied from 1–1.95 mg/unit and 0.3–5 mg/unit for supplements marketed in Europe (Spain) and the US, respectively. Four out of 17 supplements showed significant deviations from melatonin content declared on the label (from −60% to −20%). Only five out of the eight supplements purchased in Spain actually met the qualifications needed to claim to reduce the time to fall asleep. Another study analyzed the actual melatonin content (and presence of contaminants) in 31 melatonin supplements purchased from groceries and pharmacies in one city in Canada [22]. Melatonin content varied from −83% to +478% of labeled melatonin and approximately three-fourths had melatonin concentration ≤10% of what was claimed. Worse yet, the content of melatonin between lots of the same product varied by as much as 465%. An additional 26% of the 31 melatonin supplements were found to contain serotonin.
Concerning resveratrol, 14 brands of resveratrol-containing nutraceuticals were evaluated [23]. The 14 preparations were purchased directly from online stores during 2010 and were analysed before their expiry dates. Only five out of 14 brands had near label values, compliant with Good Manufacturing Practices (GMP) requirements (95%–105% content of active constituent), four products were slightly out of this range (83%–111%) and three were in the 8%–64% range. Two samples were below the limit of detection. The greater the difference between actual and labeled resveratrol content, the lower the antioxidant and antiproliferative activity strength.
With regard to selenium, one study analysed six different brands of yeast-based selenium food supplements that were obtained from local stores [24]. These supplements were treated with milder extraction and hydrolysis conditions to analyse for the expected selenomethionine content. Only two brands had high levels of selenomethionine, one brand appeared to contain all inorganic selenium, and one brand appeared to contain greater than half inorganic selenium despite label claims of content being only selenomethionine.
2. Carnitine: Compound and Physiology
Carnitine is a quaternary ammonium compound (3-Hydroxy-4-(trimethylazaniumyl) butanoate) that is ubiquitous in tissues and biological fluids of mammals [25]. The natural enantiomer is l-carnitine, which acts as an obligatory cofactor for β-oxidation of fatty acids by facilitating the transport of the long-chain fatty acids across the mitochondrial inner membrane as acyl-carnitine esters. This oxidation liberates energy via the production of ATP in the respiratory chain, thus playing a role in cell’s energy metabolism. Particularly, l-carnitine exerted a physiological benefit with a positive impact on cardiac function through reduced oxidative stress, inflammation and necrosis of cardiac myocytes. [26]. Only 25% of the body stores of carnitine come from biosynthesis and 75% comes from the diet. The main source is red meat and dairy products. Muscles are the most prominent carnitine depository since they store about 95% of the 120 mmol total amount contained in the adult human body, and the concentration in skeletal muscle (3.5 mmol/L) is 70-fold greater than that in plasma.
The main interest in carnitine supplementation comes from athletes and other physical exercise performers [27]. Thus, repeated-dose carnitine supplements may increase skeletal muscle content. For instance, long-distance runners given a daily dose of 2 g carnitine for 28 days and subjected to a four-week training period [28] increased skeletal muscle carnitine by approximately 13% as compared to a decrease of about 10% in placebo-treated athletes. In other athletes, supplementation with 1 g/day carnitine for 120 days of training increased carnitine concentrations in skeletal muscle by an average of 9% compared to a decrease of 5% in the placebo-treated athletes [29]. Carnitine is critical for normal skeletal muscle bioenergetics [30,31,32], and skeletal muscles suffer seriously in states of carnitine deficiency. A relative carnitine deficiency can occur in athletes as a result of increased energy metabolism, unbalanced nutrition, decreased skeletal muscle content and increased renal excretion of carnitine. The important energetic role of carnitine, the relative deficiency associated with sustained physical exercise, and the fact that carnitine is a natural compound, has led healthy subjects aiming to improve their exercise performance to conclude that “more carnitine should be better [30,31,32], but basically this was proven to be without any beneficial effect.
Carnitine and Thyroid Function
A German group of authors conducted pivotal clinical studies as early as 1959 in a very limited number of patients with Graves’ disease, using a mixture of the two isomers (l-and d-carnitine) [33]. The first patient was a 53-year-old bedridden woman with very severe Graves’ disease and nervousness, insomnia, weight loss, sweating, tachycardia and Graves’ orbitopathy. Basal metabolic rate (BMR) was +82%, and she was administered 1 g/d d,l-carnitine. After 10 days, BMR was unchanged but one week later it fell to +59%. Five weeks after starting d,l-carnitine, BMR was still +50% and the authors switched to the naturally occurring l-carnitine. After only 10 days BMR dropped more rapidly to +8% with associate improvement in general well-being and heart rate. Atrial fibrillation disappeared and heart rate was 80–90 beats/min. To prove that the improvement was due to l-carnitine, it was withdrawn in the 7th week from admission. BMR rose to +39%, but after rechallenge with l-carnitine it fell again to +18% [33].
In the English-language literature, the first three monotherapy carnitine-treated hyperthyroid patients were reported in the mid-1960s [34]. The authors found that patients became clinically euthyroid without any consistent changes in the thyroid function tests, thus supporting the notion that the antithyroid effect of carnitine is one of peripheral antagonism of thyroid hormone, rather than a direct inhibition of thyroid gland function [35]. This was consistent with human tissue culture experiments where l-carnitine inhibited both cell entry and, to a greater extent, nuclear entry of both T3 and T4 [36]. These data are consistent with carnitine being a peripheral antagonist of thyroid hormone action, with a site of inhibition at or before the nuclear envelope [36].
The first controlled clinical trial addressing the value of l-carnitine in antagonizing elevated circulating levels of thyroid hormones was conducted in 50 women under Thyroid stimulating hormone (TSH)-suppressive l-T4 therapy for cytologically benign thyroid nodules who received a simultaneous treatment for six months with placebo (n = 10), or for given periods of time with l-carnitine (2g/d or 4 g/d to test dose-dependence) [37]. Evaluation by both extensive clinical and biochemical assessment demonstrated positive effects with the exception of osteocalcin, which increased further during l-carnitine administration and partial exception of total cholesterol (minimal or no increase during l-carnitine administration). Serum FT3, FT4 and TSH remained unchanged throughout the 180 day-duration of the trial. Thus, there was no antagonism from l-carnitine on the negative feedback that thyroid hormones exert on thyrotropin releasing hormone (TRH)/TSH. In addition to the hypothalamic TRH-producing neurons and the pituitary thyrotropin, also osteoblasts were refractory to the thyroid-hormone antagonizing effect of l-carnitine (see above). Thus, l-carnitine synergized with thyroid hormone on the osteoblasts to increase osteocalcin serum concentrations. The favorable effect on the osteoblasts was supported by measuring femur and lumbar bone density by dual-energy-X-ray absorptiometry [37].
More recent cases of severe forms of Graves’ disease-related hyperthyroidism, including thyroid storms, were treated successfully with l-carnitine [38,39,40]. Recently, a pilot study indicated the beneficial effects of a combination of l-carnitine and selenium supplementation in subclinical hyperthyroidism [41]. A rationale for a beneficial effect of l-carnitine supplementation in hyperthyroid patients seems likely because increased levels of thyroid hormones deprive the tissue deposits of l-carnitine itself [42], which is further substantiated by the finding of decreased concentrations of carnitine in the skeletal muscles of hyperthyroid patients. Interestingly, trendwise decreased concentrations of carnitine were found in skeletal muscles of hypothyroid patients [43], which were restored upon regaining euthyroidism. Therefore, decreased concentrations of carnitine in skeletal muscles may contribute to myopathy associated with either hypothyroidism or hyperthyroidism.
Sixty thyroid-hormone adequately replaced hypothyroid Korean patients (age 50.0 ± 9.2 years, 57 females) continued to complain of fatigue [44]. These patients were given l-carnitine (990 mg l-carnitine twice daily; n = 30) or placebo (n = 30) for 12 weeks. After 12 weeks, although neither the fatigue severity score nor the physical fatigue score changed significantly after 12 weeks, but the mental fatigue score was significantly improved by treatment with l-carnitine compared with placebo (p < 0.01). In subgroups, both the physical and mental fatigue scores improved significantly in patients younger than 50 years and those with free T3 ≥ 4.0 pg/mL by treatment with l-carnitine compared with placebo. Other case-based studies have indicated a benefit from l-carnitine on hypothyroid symptoms, but all of them have been case-based [45], while other studies may support benefits in the corticosteroid hormone setting [46].
3. Inositol: Compound and Physiology
Inositol is a water-soluble compound closely associated with the vitamin B group (also known as vitamin B8) [47]. Inositol is a carbohydrate which has a taste half as sweet as that of sucrose. Inositol has long been known for its metabolic effects in humans, where it plays a part in the synthesis of secondary messengers within cells. It is an essential component of the phospholipids that makes up cellular membranes and is found in virtually all cells. The most abundant form of the nutrient is myo-inositol. It assists in the transmission of nerve signals, helps to transport lipids within the body, and is also critical for the proper action of insulin and maintenance of cellular calcium balance. Foods containing the highest concentrations of myo-inositol include fruits, beans, grains and nuts. However, in grains, it is in a non-available form called phytate. The more bioavailable form of inositol comes from lecithin. Inositol is a necessary component of all cellular membranes. It is a member of the B-vitamin family that contributes to muscular and nerve function and participates in the metabolism of fats in the liver. Myo-inositol is the most abundant form of this nutrient, with its highest concentrations being found in the brain and central nervous system. Myo-inositol in particular is a versatile nutrient for the promotion of emotional and mental wellness, healthy eating patterns, and restful sleep through its critical role in neurotransmitter messaging systems. In addition, it is an important nutritional element for the maintenance of ovarian health and normal blood sugar maintenance, especially in women. Inositol is a non-essential member of the B-complex family with dietary sources from both animal and plant foods. The form of inositol used in this product is myo-inositol, the most abundant form of this nutrient. Inositol is found in all cell membranes, with the highest concentrations in the brain and central nervous system, where it plays an important role in neurotransmitter signaling. Inositol is also critical for the proper action of insulin, lipid metabolism, and for the maintenance of cellular calcium balance. Inositol is a necessary component of all cellular membranes. It is a member of the inositols are marketed as beneficial nutraceutics for improving mood and for the treatment of polycystic ovary syndrome [20]. A significant difference in the myo-inositol content of available products, and there are no regulations to ensure homogenous quality and accuracy [20].
Inositol and Thyroid Function/Autoimmunity
Inositols are essential for the signaling of hormones such as insulin, gonadotropins (follicle stimulating hormone [FSH] and luteinizing hormone [LH]), and TSH. In the thyroid, imbalances in the inositol metabolism can impair thyroidal hormone biosynthesis, storage and secretion [47]. TSH signaling is rather complex involving two different signal cascades. One branch of the signal cascade involves as second messenger cyclic AMP (cAMP), while another branch is inositol-dependent [48]. In a controlled trial, 48 women with autoimmune subclinical hypothyroidism were randomized to treatment with either selenomethionine alone or selenomethionine plus myo-inositol. The authors demonstrated that patients with autoimmune thyroiditis and subclinical hypothyroidism, treated with myo-inositol and selenomethionine, had a reduction of the increased TSH, which selenomethionine supplementation alone was not able to promote. However, the concentration of both thyroperoxidase and thyroglobulin autoantibodies (TPOAb and TgAb) declined in both groups [48]. In a subsequent study of 86 patients with Hashimoto’s thyroiditis and subclinical hypothyroidism, the same authors found that the administration of myo-inositol and selenomethionine for six months significantly decreased TSH, TPOAb, and TgAb concentrations, while at the same time enhancing thyroid hormones and personal wellbeing, thereby restoring euthyroidism in patients diagnosed with autoimmune thyroiditis [49]. This was confirmed in a larger study of 168 patients with Hashimoto’s thyroiditis and subclinical hypothyroidism (TSH 3–6 mU/L) [50].
The mechanism of this effect might be through immune modulation rather than through thyroid function per se [51]. Using the afore-mentioned combined treatment in 22 patients with autoimmune thyroiditis, the initial TSH levels in the high normal range (2.1 < TSH < 4.0) significantly declined, suggesting that the combined treatment can reduce the risk of progression to hypothyroidism in subjects with autoimmune thyroid diseases. Antithyroid autoantibody levels also declined and, moreover, the suspected immune-modulatory effect was confirmed by the finding that the concentration of the chemokine CXCL10 also declined. Studies are, however, awaited to extend the observations in a larger population, to evaluate the effect on the quality of life, and to study the mechanism of the effect on chemokines.
Very recently, thyroid nodular disease also seemed to improve after the combined treatment with myo-inositol and selenomethionine [52], but this also needs confirmation. Final data in this study was analyzed from 34 patients with subclinical hypothyroidism: in 76% of mixed thyroid nodules a significant reduction of their size was observed and 56% of them significantly regressed nodule stiffness following oral supplementation with the combined nutraceutics for six months. The mean number of mixed thyroid nodules shifted from 1.4 ± 0.2 to 1.1 ± 0.2 (p ≤ 0.05) and the TSH concentrations dropped from 4.2 ± 0.2 mIU/L at baseline to 2.1 ± 0.2 mIU/L post-treatment (p < 0.001). In the control group, 38% of the thyroid nodules reduced their diameter but TSH concentrations significantly increased up to the threshold after six months (from 4.0 ± 0.2 mIU/L to 4.3 ± 0.2 mIU/L, p ≤ 0.05). However, further studies are required, both in vitro and in vivo, in order to investigate the mechanism of this effect on the one hand, and a possible clinical treatment use of myo-inositol plus selenomethionine for the general management of thyroid nodules on the other.
4. Melatonin: Compound and Physiology
The isolation of melatonin was first reported in 1958 [53]. Since the demonstration that pineal melatonin synthesis reflects both daily and seasonal time, melatonin has become a key element of chronobiology research. In mammals, pineal melatonin is essential for transducing day-length information into seasonal physiological responses. Due to its lipophilic nature, melatonin is able to cross the placenta and is believed to regulate multiple aspects of perinatal physiology. The endogenous daily melatonin rhythm is also likely to play a role in the maintenance of synchrony between circadian clocks throughout the adult body. Pharmacological doses of melatonin are effective in resetting circadian rhythms if taken at an appropriate time of day and can acutely regulate factors such as body temperature and alertness, especially when taken during the day. Despite the extensive literature on melatonin physiology, several key questions remain unanswered. Particularly the amplitude of melatonin rhythms has recently been associated with diseases such as type 2 diabetes mellitus but the physiological significance of melatonin rhythm amplitude remains poorly understood.
As a nutraceutical, melatonin is easily available over the counter and is marketed to regulate the sleep pattern and adaptation to time zone differences among numerous other conditions.
Melatonin and Thyroid Function
Melatonin has antioxidant properties, which is one of the reasons why it is assumed to be beneficial for many disease conditions. However, very few human studies exist, and they are primarily of a physiological nature. One such study considers several endocrine and immune interactions in healthy persons at different ages [54] and found statistically significant time-qualified correlations among lymphocyte subset percentages and hormone serum levels in the young and middle aged and one could speculate that the phenomenon of lymphocyte subpopulation redistribution may be more complex, and may involve other hormones such as TRH, TSH, GH (growth hormone), IGF1 (insulin-like growth factor 1), monoamines such as melatonin, cytokines such as IL2 (Interleukin 2), and chemokines. The aging of immune system function may be related to the alteration of circadian rhythmicity, with a loss of interaction among key lymphocyte subsets, immunomodulating hormones, as well as cytokines/chemokines.
Thirty-six perimenopausal and 18 postmenopausal women between 42 and 62 years of age with no pathology or medication were selected for a randomized study of melatonin or placebo at bedtime (22:00–00:00). The melatonin concentration was measured in saliva to divide the participants into low, medium, and high-melatonin subjects [55]. Three- and six-months later, blood was taken for the determination of pituitary (LH and FSH), ovarian, and thyroid hormones (T3 and T4). The results showed that women low in melatonin after treatment with melatonin significantly increased thyroid hormones levels and improved gonadal functions [55]. These results were confirmed by the same authors in another study where peri- and menopausal women (N = 139) took a daily dose of 3 mg synthetic melatonin or placebo for 6 months. Melatonin concentrations were determined from five daily saliva samples at fixed times while other hormone levels were determined from blood samples three times over the six-month period [56]. The conclusion was that the six-months treatment with melatonin produced a remarkable and highly significant improvement of thyroid function, positive changes of gonadotropins towards more juvenile levels, and the abrogation of menopause-related depression.
In 40 menopausal women the combination of myo-inositol plus melatonin seemed to positively affect glucose metabolism. Myo-inositol alone seemed to improve thyroid function, while addition of melatonin increased the serum TSH concentration [57]. The reason for this is unknown, but all melatonin products warn against worsening of autoimmune diseases on basis of its potential effect on the immune system. Recently, SNPs related to melatonin receptor gene polymorphism haplotypes were associated with susceptibility to Graves’ disease in an ethnic Chinese population and thus support the involvement of the melatonin pathway in the pathogenesis of this autoimmune thyroid disease [58].
In conclusion, there is to date no controlled trials to substantiate a use of melatonin for general thyroid health improvement.
5. Resveratrol: Compound and Physiology
Resveratrol (3,4′,5-trihydroxy-trans-stilbene) belongs to the flavonoids family and is a major natural polyphenolic compound found in several fruit and vegetables such as grapes, peanuts, and peanut sprouts. It seems to play an important role as a therapeutic and chemopreventive agent used in the treatment of various illnesses [59,60] and has therefore recently gained much attention among health professionals as well as other nutrition experts. Resveratrol exhibits effects against several cancers [61,62] through different pathways and, furthermore, it has antidiabetic, anti-inflammatory, and antioxidant effects. The cardiovascular protective capacities of resveratrol are believed to be associated with multiple molecular targets such as inflammation, oxidative stress, apoptosis, mitochondrial dysfunction, angiogenesis and platelet aggregation [59].
Similarly, resveratrol is a potent scavenger for free radicals. The high efficiency of resveratrol might be due to the three hydroxyl groups in its structure. Thus, the use of resveratrol as a health-promoting dietary supplement is rapidly increasing in today’s market. Many reports have shown that resveratrol offers a wide range of preventive and therapeutic alternatives against various diseases including different types of cancer.
Resveratrol is a member of a family of enzymes, under the general name of stilbene synthase, which makes up part of a larger family of proteins with numerous functions. Notably, its chemical structure resembles that of l-T4, however it is not clear if this has any functional implications [63]. Resveratrol synthase is developed from chalcone synthase via gene duplication and mutations. The absorption in humans is approximately 75% (delayed by food) by trans-epithelial diffusion, while tissue accumulation enhances efficacy at target sites.
Resveratrol and Thyroid Function
Resveratrol may arrest the proliferation of thyroid cancer cells by increasing the abundance and phosphorylation of p53 [64,65,66]. Moreover, resveratrol mediates the regulation of TSH while, due to its effects on iodine trapping, it shows promise as a prospective anti-thyroid drug. On the other hand, these effects also resulted in a pronounced proliferative action on thyrocytes and resveratrol may therefore be a thyroid disrupting compound [67]. No clinical studies on the compound’s effect on the thyroid has been performed in humans, so all available evidence is based on animal and in vitro cellular studies.
Finally, resveratrol as an antioxidant agent is a free radical scavenger and this property can be of interest in thyroid disease states that are accompanied by increased production of hydrogen peroxide and radical oxygen species, such as autoimmune thyroiditis and hyperthyroidism [68]. Proper randomized clinical trials would, however, be required before implementing any use.
Resveratrol supplements can be easily purchased over the counter but they are not regulated by the FDA or any other health authority. Most resveratrol capsules sold in the U.S. contain extracts from an Asian plant called Polygonum cuspidatum. Other resveratrol supplements are made from red wine or red grape extracts. The dosages in most resveratrol supplements typically contain 250 to 500 milligrams, which is much lower than the amounts that have been shown beneficial in research (2000 milligrams of resveratrol or more a day).
6. Selenium: Compound and Physiology
Selenium is a non-metal chemical element that is an essential micronutrient. Selenium salts are toxic in large amounts, but trace amounts are necessary for cellular function in many organisms, including all animals. Dietary selenium comes from nuts, cereals, and mushrooms. Brazil nuts are the richest dietary source (though this is soil-dependent since the Brazil nut does not require high levels of the element for its own needs). Selenium is an ingredient in many multivitamins and other dietary supplements. It is a component of the antioxidant enzymes glutathione peroxidase and thioredoxin reductase, which indirectly reduce certain oxidized molecules in animals and some plants. It is also found in three deiodinase enzymes, which convert one thyroid hormone to another. In living systems, selenium is found in the amino acids selenomethionine, selenocysteine, and methylselenocysteine.
The U.S. recommended dietary allowance (RDA) for teenagers and adults is 55 µg/day. Selenium as a dietary supplement is available in many forms, including multi-vitamins/mineral supplements, which typically contain 55 or 70 µg/serving. Selenium-specific supplements typically contain either 100 or 200 µg/serving. In June 2015, the U.S. FDA published its final rule establishing the requirement of minimum and maximum levels of selenium in infant formula. The reference values of EFSA for selenium range from 15 µg/day for children aged one to three years to 70 µg/day for adolescents aged 15–17 years [69]. The selenium content in the human body is believed to be in the range of 13–20 milligram [70].
Selenium food supplements are most efficient as yeast-based selenomethionine, but the contents are not standardized or under any control. For instance, six different brands of yeast-based selenium food supplements were analysed for the expected selenomethionine content [23]. Only two brands had high levels of selenomethionine; one brand appeared to contain only inorganic selenium, and one brand appeared to contain more than half inorganic selenium despite label claims of content being only selenomethionine. Nevertheless, selenium supplementation is increasingly prescribed by endocrinologists as recently documented for Italian endocrinologists [70]. In detail, approximately one in four respondents use selenium often/always, with only one in either use never. Rates were approximately one-fourth of respondents prescribing selenium often/always in Hashimoto’s thyroiditis, and one-fifth prescribing selenium in the case presented. In patients with autoimmune thyroiditis (AIT) who are planning pregnancy or are already pregnant, approximately 40% of respondents suggest selenium use [71]. It is worth underlining that the American Thyroid Association (ATA) pregnancy guideline reported that “selenium supplementation is not recommended for the treatment of TPOAb-positive women during pregnancy” [72].
Selenium and Thyroid Function/Autoimmunity
Among all tissues, the thyroid gland has the highest concentration of selenium, of which much is stored in the thyrocytes as the selenoproteins [73,74]: deiodinases (DI1, DI2), glutathion peroxidase (GPx1, GPx3, GPx4), and thioredoxin reductases (TR1, TR2). Both the thyroid gland and all other cells that are dependent of thyroid hormone for proper function use selenium as a cofactor for three of the four known types of thyroid hormone deiodinases, which can both activate and deactivate thyroid hormones and their metabolites—the iodothyronine deiodinases are the subfamily of deiodinase enzymes that use selenium, as does the otherwise rare amino acid selenocysteine. Only iodotyrosine deiodinase does not use selenium.
Adequate selenium intake is required for normal function of thyrocytes and the angiofollicular units in thyroid hormone biosynthesis and storage. Inadequate selenium intake has been associated with increased thyroid volume in females, but not males in one study [75], and in a larger Danish population, this negative correlation between selenium status and thyroid volume was confirmed, and there was, furthermore, a trend toward increased numbers of thyroid nodules with inadequate selenium status [74,76]. Adequate selenium intake, with respect to proper thyroid function, can be monitored by the analysis of serum or plasma selenoproteins such as selenoprotein P or plasma GPx3 [74,77,78]. Intoxication has been reported in several places in China from dietary intake and soil contamination [79,80]. Measurement of these variables is becoming more important in the view of the increased interest in selenium supplementation in various patient groups particularly with autoimmune thyroid diseases (see below) and since there is a risk of overdosing by general too high doses on the one hand and supplementation of selenium sufficient individuals on the other. The U-shaped curve of beneficial effects from selenium concentrations, i.e., exhibiting major advantages in selenium-deficient individuals but specific health risks in those with selenium excess should be seriously considered [81].
Selenium status has been shown to affect immune functions, e.g., T cell differentiation, and selenium deficiency has been associated with Th3 cells/markers, while higher selenium concentrations seem to favor an increased Th2 and Treg response [82]. These observations are thus in keeping with the suggestion of beneficial effects of selenium supplementation in autoimmune diseases of the thyroid [73,83]. Newly diagnosed autoimmune hyperthyroidism, Graves’ disease, has been associated with low selenium concentrations [84], an observation which has fuelled several interventional treatment studies of selenium supplementation as adjunctive to antithyroid drugs in Graves’ disease [85,86,87,88]. A very recent systematic review and meta-analysis of 10 randomized clinical trials could not substantiate a systematic effect of selenium supplementation as an adjunctive treatment in Graves’ disease [89]. Generally, the studies were all underpowered, of too short a duration, and with too broad clinical characteristics of the patients, and the issue is therefore yet to be resolved—results from larger ongoing prospective studies are awaited [90].
Concerning the subpopulations of Graves’ disease, however, a prospective case-control study demonstrated lower serum selenium concentrations in patients with Graves’ orbitopathy compared to Graves’ patients without orbitopathy in an Australian study population with marginal selenium status [91]. Against this background, relative selenium deficiency may be an independent risk factor for orbitopathy in patients with Graves’ diseases. This has been further substantiated by one major multicentric prospective, placebo and serum-controlled study of Graves’ patients with orbitopathy, with demonstration of improved quality of life and disease activity scores [92].
Several placebo-controlled and double-blind studies, both observational and prospective, have been performed to demonstrate the improved quality of life, wellbeing, thyroid hormone status, and disease symptoms of chronic autoimmune thyroiditis of the Hashimoto type with or without hypothyroidism. Although many studies have consistently demonstrated a reduction in thyroid autoantibody concentrations by selenium supplementation, including some compared with control/placebo [93,94,95,96], recent meta-analyses found insufficient evidence for the clinical efficacy of selenium supplementation in chronic autoimmune thyroiditis [97,98]. Hopefully, future trials can ultimately provide reliable evidence to help inform clinical decision making. Results were less optimistic than the individual study results, many of which were, however, underpowered, and therefore, in this autoimmune patient group, results are unclear and further ongoing study results are awaited [99].
In women at risk of postpartum thyroiditis, adequate selenium status prevents its development. In a prospective placebo-controlled double-blind prevention study [100], there were fewer cases of postpartum thyroiditis—these results, however, have not been confirmed in other studies [73,101].
Finally, there has been no indication of an increased risk of thyroid cancer in either selenium deficiency or with supplementation of selenium [74].
In conclusion, selenium status has a high impact on normal thyroid development and function, and it is still a potential candidate for improvement of clinical markers and quality of life in some situations of autoimmune thyroid diseases by supplementation, e.g., Graves’ orbitopathy and possibly postpartum thyroiditis. However, more solid evidence is awaited until firm conclusions can be made concerning recommendations for global routine clinical use.
7. Perspective and Conclusions
As clinicians, we often see patients who are taking all sorts of supplements with the hope of improving their health and medical conditions, as well as simply feeling better.
Thyroid supplements attract a disproportionately large amount of attention, just as the thyroid gland gets “blamed” for multiple symptoms. There are truths and myths that this review had tried to clarify. Of the numerous nutraceuticals out there for thyroid disease management, we focused on the common or popular ones we encounter in the clinical practice.
Clinicians should acknowledge that over 30% of our patients are using supplements and thus should inquire about them during our office encounters. Apart from improving their general health, patients are using these alleged thyroid supplements to help “improve their metabolism, have more energy, and to lose weight”.
It is important that we do not just dismiss these patients, but rather have honest discussions about the claimed benefits and potential risks. Physicians would do well to familiarize themselves with the main supplements being used, and also to know the scientific evidence available to support or refute these claims. More importantly, physicians should understand the potential risks or side effects in order to properly counsel patients about their use.
Based on the literature reviewed in the preceding sections, the evidence for the clinical use and potential benefit of the nutraceuticals addressed in this paper is summarized in . It is, however, worth noting that very few studies have been randomized clinical trials and generally all the studies have lacked proper power and even attempts to perform power calculations including the few randomized clinical trials. For selenium, two randomized, properly powered, placebo controlled clinical trials are ongoing and results are awaited [89,98]. Similar studies are required also for the most relevant nutraceuticals with a possible influence on the thyroid, in order to provide proper guidance both to patients and clinicians.
Table 4
Summary of evidence for clinical use of the nutraceuticals reviewed here in the thyroid setting *.
Question: Is There Evidence for Clinical Use of …?
Answer
Carnitine
Currently available evidence supports the usefulness of l-carnitine in hyperthyroid patients. Carnitine ameliorates a number of symptoms and signs, including cardiac arrhythmia. Case reports have shown benefits even in the setting of thyroid storm. However, no changes in thyroid function tests were reported. 
One practical setting for the use of l-carnitine (two grams per day) is the control of hyperthyroidism symptomatology when the patients need to take low doses of antithyroid drugs. Only one Korean study is currently available for hypothyroidism, thus precluding conclusions.
Inositols
Only in one study, MI alone (2 g twice a day) or MI plus melatonin (2 g/d MI plus 3 g/d melatonin) were given in two groups of euthyroid postmenopausal women, and serum FT4 and TSH evaluated. MI alone caused an almost 3.5% increase in serum FT4 and a 10% decrease in serum TSH. This contrasted with the opposite changes (3.5% decrease in serum FT4 and almost 10% increase in serum TSH) observed in the group under MI plus melatonin.
Few studies have been conducted only in one Western country (Italy), and with the combination of MI plus selenium or MI plus carnitine. Supplementation with the first combination has been used in the setting of patients with Hashimoto’s thyroiditis related SCHypo, and it decreased both serum thyroid autoantibodies and TSH. The combination of MI plus carnitine was only investigated in one study of patients with SCHyper, thus precluding conclusions.
Melatonin
There has been interest in melatonin and autoimmunity and the thyroid gland has been implicated in the discussion. It is thought that melatonin may have a paracrine role and in thyroid disease under a condition of oxidative stress may reduce the processes involved in thyroid antoimmunity. However, there are no controlled trials or definite data to show conclusively that melatonin can be beneficial in thyroid disease.
Resveratrol
No answer can be given, simply for lack of studies.
Selenium
Benefits have been demonstrated for mild forms of Graves’ ophthalmopathy. Benefits for the clinical course of GD itself are controversial. In the setting of HT, a benefit has been shown more on serum thyroid autoantibodies than on thyroid function. There is only one study on the benefit given by selenium supplementation, both in terms of serum thyroid autoantibodies and thyroid dysfunction, in the setting of PPT. For the combinations of selenium with MI see above.
Acknowledgments
UF-R’s research salary is sponsored by an unrestricted research grant from the NovoNordisk Foundation. This paper received no administrative or technical support.
Appendix A
Table A1
Information on the dietary supplements provided by the Food and Drug Administration *.
Questions
Answers
What is a dietary supplement? §
Congress defined the term “dietary supplement” in the Dietary Supplement Health and Education Act (DSHEA) of 1994. A dietary supplement is a product taken by mouth that contains a “dietary ingredient” intended to supplement the diet. The “dietary ingredients” in these products may include vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites. Dietary supplements can also be extracts or concentrates and may be found in many forms such as tablets, capsules, softgels, gelcaps, liquids, or powders. They can also be in other forms, such as a bar, but if they are, information on their label must not represent the product as a conventional food or a sole item of a meal or diet. Whatever their form may be, DSHEA places dietary supplements in a special category under the general umbrella of “foods”, not drugs, and requires that every supplement be labeled a dietary supplement.
What is a “new dietary ingredient” in a dietary supplement? §
The Dietary Supplement Health and Education Act (DSHEA) of 1994 defined both of the terms “dietary ingredient” and “new dietary ingredient” as components of dietary supplements. In order for an ingredient of a dietary supplement to be a “dietary ingredient,” it must be one or any combination of the following substances:
a vitamin,
a mineral,
an herb or other botanical,
an amino acid,
a dietary substance for use by man to supplement the diet by increasing the total dietary intake (e.g., enzymes or tissues from organs or glands), or a concentrate, metabolite, constituent or extract.
A “new dietary ingredient” is one that meets the above definition for a “dietary ingredient” and was not sold in the U.S. in a dietary supplement before 15 October 1994.
What are the benefits of dietary supplements?
Some supplements can help assure that you get enough of the vital substances the body needs to function; others may help reduce the risk of disease. But supplements should not replace complete meals which are necessary for a healthful diet–so, be sure you eat a variety of foods as well.
Unlike drugs, supplements are not permitted to be marketed for the purpose of treating, diagnosing, preventing, or curing diseases. That means supplements should not make disease claims, such as “lowers high cholesterol” or “treats heart disease.” Claims like these cannot be legitimately made for dietary supplements.
Are there any risks in taking supplements?
Yes. Many supplements contain active ingredients that have strong biological effects in the body. This could make them unsafe in some situations and hurt or complicate your health. For example, the following actions could lead to harmful–even life-threatening–consequences.
Combining supplements
Using supplements with medicines (whether prescription or over the counter)
Substituting supplements for prescription medicines
Taking too much of some supplements, such as vitamin A, vitamin D, or iron
Some supplements can also have unwanted effects before, during, and after surgery. So, be sure to inform your healthcare provider, including your pharmacist about any supplements you are taking.
Some Common Dietary Supplements
Calcium
Echinacea
Fish Oil
Glucosamine and/or
Chondroitin Sulphate
Garlic
Vitamin D
St. John’s Wort
Saw Palmetto
Ginkgo
Green Tea
Note: These examples do not represent either an endorsement or approval by FDA.
How can I find out more about the dietary supplement I’m taking?
Dietary supplement labels must include name and location information for the manufacturer or distributor.
If you want to know more about the product that you are taking, check with the manufacturer or distributor about:
Information to support the claims of the product.
Information on the safety and effectiveness of the ingredients in the product.
Report Problems to FDA
Notify the FDA if the use of a dietary supplement caused you or a family member to have a serious reaction or illness (even if you are not certain that the product was the cause, or you did not visit a doctor or clinic).
Follow these steps:
Stop using the product.
Contact your healthcare provider to find out how to take care of the problem.
Report problems to FDA in either of these ways:
Contact the Consumer Complaint Coordinator in your area.
File a safety report online through the Safety Reporting Portal.
Author Contributions
S.B., U.F.-R. and E.A. conceptualized, searched literature and wrote the first versions of the manuscript. D.B. took care of the final update, revision and editing.
Funding
This work received no external funding.
Conflicts of Interest
The authors declare no conflict of interest.
References
6. European Parliament  Regulation EU 2015/2283 of the European Parliament and of the Council of 25 November 2015 on novel foods, amending Regulation (EU) No 1169/2011 of the European Parliament and of the Council and repealing Regulation (EC) No 258/97 of the European Parliament and of the Council and Commission Regulation (EC) No 1852/2001.  [(accessed on 3 September 2019)]; Available online:  https://eur-lex.europa.eu/legal-content/en/TXT/?uri=CELEX%3A32015R2283.7. DSHEA 1994  United States Food and Drug Administration (FDA). Dietary Supplement Health and Education Act (DSHEA). U.S. Department of Health and Human Services. United States. Public Law 103–417.  [(accessed on 3 September 2019)]; Available online:  https://ods.od.nih.gov/About/DSHEA_Wording.aspx.10. Wootan G.D., Brittain P.M.  Detox Diets for Dummies. Wiley Publishing, Inc.; Hoboken, NJ, USA: 2010. p. 88. [Google Scholar]15. Yoshino J., Conte C., Fontana L., Mittendorfer B., Imai S., Schechtman K.B., Gu C., Kunz I., Rossi Fanelli F., Patterson B.W., et al.  Resveratrol supplementation does not improve metabolic function in nonobese women with normal glucose tolerance. Cell Metab. 2012;16:658–664. doi: 10.1016/j.cmet.2012.09.015. [PMC free article] [PubMed] [CrossRef] [Google Scholar]17. Lockwood G.B. The quality of commercially available nutraceutical supplements and food sources. J. Pharm. Pharmacol. 2011;63:3–10. doi: 10.1111/j.2042-7158.2010.01159.x. [PubMed] [CrossRef] [Google Scholar]18. Kang G.Y., Parks J.R., Fileta B., Chang A., Abdel-Rahim M.M., Burch H.B., Bernet V.J. Thyroxine and triiodothyronine content in commercially available thyroid health supplements. Thyroid. 2013;23:1233–1237. doi: 10.1089/thy.2013.0101. [PubMed] [CrossRef] [Google Scholar]19. Millington D.S., Dubag G. Dietary supplement L-carnitine: Analysis of different brands to determine bioavailability and content. Clin. Res. Reg. Affairs. 1993;10:71–80. [Google Scholar]20. Papaleo V., Molgora M., Quaranta L., Pellegrino M., De Michele F. Myo-inositol products in polycystic ovary syndrome (PCOS) treatment: Quality, labeling accuracy, and cost comparison. Eur. Rev. Med. Pharmacol. Sci. 2011;15:165–174. [PubMed] [Google Scholar]21. Cerezo A.B., Leal A., Alvarez-Fernandez M.A., Hornedo-Ortega R., Troncoso A.M., Garcia-Parrilla M.C. Quality control and determination of melatonin in food supplements. J. Food Compos. Anal. 2016;45:80–86. doi: 10.1016/j.jfca.2015.09.013. [CrossRef] [Google Scholar]22. Erland L.A., Sazena P.K. Melatonin Natural Health Products and Supplements: Presence of Serotonin and Significant Variability of Melatonin Content. J. Clin. Sleep. Med. 2017;13:275–281. doi: 10.5664/jcsm.6462. [PMC free article] [PubMed] [CrossRef] [Google Scholar]23. Rossi D., Guerrini A., Bruni R., Brognara E., Borgatti M., Gambari R., Maietti S., Sacchetti G. trans-Resveratrol in nutraceuticals: Issues in retail quality and effectiveness. Molecules. 2012;17:12393–12405. doi: 10.3390/molecules171012393. [PMC free article] [PubMed] [CrossRef] [Google Scholar]24. B’Hymer C., Caruso J.A. Evaluation of yeast-based selenium food supplements using high-performance liquid chromatography and inductively coupled plasma mass spectrometry. J. Anal. At. Spectrom. 2000;15:1531–1539. doi: 10.1039/b006437h. [CrossRef] [Google Scholar]25. Hoppel C.  The physiologic role of carnitine. In: Ferrari R., Di Mauro S., Sherwood G., editors. L-Carnitine and its Role in Medicine: From Function to Therapy. Academic Press; San Diego, CA, USA: 1990. pp. 5–19. [Google Scholar]26. Wang Z.Y., Liu Y.Y., Liu G.H., Lu H.B., Mao C.Y. L-Carnitine and heart disease. Life Sci. 2018;194:88–97. doi: 10.1016/j.lfs.2017.12.015. [PubMed] [CrossRef] [Google Scholar]27. Benvenga S. Effects of L-carnitine on thyroid hormone metabolism and on physical exercise tolerance. Horm. Metab. Res. 2005;37:566–571. doi: 10.1055/s-2005-870424. [PubMed] [CrossRef] [Google Scholar]28. Arenas J., Huertas R., Campos Y., Diaz A.E., Villalon J.M., Vilas E. Effects of L-carnitine on the pyruvate dehydrogenase complex and carnitine palmitoyl transferase in muscle athletes. FEBS Lett. 1994;341:91–93. doi: 10.1016/0014-5793(94)80246-7. [PubMed] [CrossRef] [Google Scholar]29. Arenas J., Ricoy J.R., Encinas A.R., Pola P., D’Iddio S., Zeviani M., Di Donato S., Corsi M. Carnitine in muscle, serum and urine of non-professional athletes; effects of physical exercise, training, and L-carnitine administration. Muscle Nerve. 1991;14:598–604. doi: 10.1002/mus.880140703. [PubMed] [CrossRef] [Google Scholar]30. Brass E.P., Hiatt W.R. The role of carnitine and carnitine supplementation during excercise in man and in individuals with special needs. J. Am. Coll. Nutr. 1998;17:207–215. doi: 10.1080/07315724.1998.10718750. [PubMed] [CrossRef] [Google Scholar]31. Brass E.P. Supplemental carnitine and exercise. Am. J. Clin. Nutr. 2000;72:618S–623S. doi: 10.1093/ajcn/72.2.618S. [PubMed] [CrossRef] [Google Scholar]32. Brass E.P. Carnitine and sports medicine: Use or abuse? Ann. NY Acad. Sci. 2004;1033:67–78. doi: 10.1196/annals.1320.006. [PubMed] [CrossRef] [Google Scholar]33. Strack E., Wortz G., Rotzsch W. Wirkungen von Carnitin bei Uberfunktion der Schildruse (Effects of Carnitine in cases of Thyroid Hyperfunction) Endocrinologie. 1959;38:218–225. [Google Scholar]34. Gilgore S.G., De Felice S.L. Evaluation of carnitine—An antagonist of thyroid hormone. J. N. Drugs. 1966;6:349–350. doi: 10.1177/009127006600600606. [PubMed] [CrossRef] [Google Scholar]35. De Felice S.L., Gilgore S.G. The antagonistic effect of carnitine in hyperthyroidism. Preliminary report. J. N. Drugs. 1966;6:351–353. doi: 10.1177/009127006600600607. [PubMed] [CrossRef] [Google Scholar]36. Benvenga S., Lakshmanan M., Trimarchi F. Carnitine is a naturally occurring inhibitor of thyroid hormone nuclear uptake. Thyroid. 2000;12:1043–1050. doi: 10.1089/thy.2000.10.1043. [PubMed] [CrossRef] [Google Scholar]37. Benvenga S., Ruggeri R.M., Russo A., Lapa D., Campenni A., Trimarchi F. Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: A randomized, double-blind, placebo-controlled clinical trial. J. Clin. Endocrinol. Metab. 2001;86:3579–3594. doi: 10.1210/jcem.86.8.7747. [PubMed] [CrossRef] [Google Scholar]38. Benvenga S., Lapa D., Cannavò S., Trimarchi F. Successive thyroid storms treated with L-carnitine and low doses of methimazole. Am. J. Med. 2003;115:417–418. doi: 10.1016/S0002-9343(03)00399-1. [PubMed] [CrossRef] [Google Scholar]39. Chee R., Agah R., Vita R., Benvenga S. Severe hyperthyroidism treated with L-carnitine, propranolol, and finally with thyroidectomy in a seriously ill cancer patient. Hormones. 2014;13:407–412. [PubMed] [Google Scholar]40. Kimmoun A., Munagamage G., Dessalles N., Gerard A., Feillet F., Levy B. Unexpected awakening from comatose thyroid storm after a single intravenous injection of L-carnitine. Intensive Care Med. 2011;37:1716–1717. doi: 10.1007/s00134-011-2293-2. [PubMed] [CrossRef] [Google Scholar]41. Nordio M. A novel treatment for subclinical hyperthyroidism: A pilot study on the beneficial effects of L-carnitine and selenium. Eur. Rev. Med. Pharmacol. Sci. 2017;21:2268–2273. [PubMed] [Google Scholar]42. Maebashi M., Kawamura N., Sato N., Imamura A., Yoshinaga K. Urinary excretion of carnitine in patients with hyperthyroidism and hypothyroidism: Augmentation by thyroid hormone. Metabolism. 1977;26:351–356. doi: 10.1016/0026-0495(77)90101-9. [PubMed] [CrossRef] [Google Scholar]43. Sinclair C., Gilchrist J.M., Hennessey J.V., Kandula M. Muscle carnitine in hypo- and hyperthyroidism. Muscle Nerve. 2005;32:357–359. doi: 10.1002/mus.20336. [PubMed] [CrossRef] [Google Scholar]44. An J.H., Kim Y.J., Kim K.J., Kim S.H., Kim N.H., Kim H.Y., Kim N.H., Choi K.M., Baik S.H., Choi D.S., et al.  L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: A randomized, double-blind, placebo-controlled trial. Endocr. J. 2016;63:885–895. doi: 10.1507/endocrj.EJ16-0109. [PubMed] [CrossRef] [Google Scholar]45. Benvenga S., Sindoni A. L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment. Endocr. J. 2016;63:937–938. doi: 10.1507/endocrj.EJ16-0374. [PubMed] [CrossRef] [Google Scholar]46. Alesci S., De Martino M.U., Mirani M., Benvenga S., Trimarchi F., Kino T., Chrousos G.P. L carnitine: A nutritional modulator of glucocorticoid receptor functions. FASEB J. 2003;17:1553–1555. doi: 10.1096/fj.02-1024fje. [PubMed] [CrossRef] [Google Scholar]47. Benvenga S., Antonelli A. Inositol(s) in thyroid function, growth and autoimmunity. Rev. Endocr. Metab. Disord. 2016;17:471–484. doi: 10.1007/s11154-016-9370-3. [PubMed] [CrossRef] [Google Scholar]48. Nordio M., Pajalich R. Combined treatment with Myo-inositol and selenium ensures euthyroidism in subclinical hypothyroidism patients with autoimmune thyroiditis. J. Thyroid Res. 2013;2013:424163. doi: 10.1155/2013/424163. [PMC free article] [PubMed] [CrossRef] [Google Scholar]49. Nordio M., Basciani S. Treatment with Myo-Inositol and Selenium Ensures Euthyroidism in Patients with Autoimmune Thyroiditis. Int. J. Endocrinol. 2017 doi: 10.1155/2017/2549491. [PMC free article] [PubMed] [CrossRef] [Google Scholar]50. Nordio M., Basciani S. Myo-inositol plus selenium supplementation restores euthyroid state in Hashimoto’s patients with subclinical hypothyroidism. Eur. Rev. Med. Pharmacol. Sci. 2017;21(Suppl. 2):51–59. [PubMed] [Google Scholar]51. Ferrari S.M., Fallahi P., Di Bari F., Vita R., Benvenga S., Antonelli A. Myo-inositol and selenium reduce the risk of developing overt hypothyroidism in patients with autoimmune thyroiditis. Eur. Rev. Med. Pharmacol. Sci. 2017;21(Suppl. 2):36–42. [PubMed] [Google Scholar]52. Nordio M., Basciani S. Evaluation of thyroid nodule characteristics in subclinical hypothyroid patients under a myo-inositol plus selenium treatment. Eur. Rev. Med. Pharmacol. Sci. 2018;22:2153–2159. [PubMed] [Google Scholar]53. Johnston J.D. 60 Years of neuroendocrinology: Regulation of mammalian neuroendocrine physiology and rhythms by melatonin. J. Endocrinol. 2015;226:T187–T198. doi: 10.1530/JOE-15-0119. [PubMed] [CrossRef] [Google Scholar]54. Mazzoccoli G., De Cata A., Carughi S., Greco A., Inglese M., Perfetto F., Tarquini R. A possible mechanism for altered immune response in the elderly. In Vivo. 2010;24:471–487. [PubMed] [Google Scholar]55. Bellipanni G., Bianchi P., Pierpaoli W., Bulian D., Ilyia E. Effects of melatonin in perimenopausal and menopausal women: A randomized and placebo controlled study. Exp. Gerontol. 2001;36:297–310. doi: 10.1016/S0531-5565(00)00217-5. [PubMed] [CrossRef] [Google Scholar]56. Bellipanni G., Di Marzo F., Blasi F., Di Marzo A. Effects of melatonin in perimenopausal and menopausal women: Our personal experience. Ann. N. Y. Acad. Sci. 2005;1057:393–402. doi: 10.1196/annals.1356.030. [PubMed] [CrossRef] [Google Scholar]57. D’Anna R., Santamaria A., Giorgianni G., Vaiarelli A., Gullo G., Di Bari F., Benvenga S. Myo-inositol and melatonin in the menopausal transition. Gynecol. Endocrinol. 2017;33:279–282. doi: 10.1080/09513590.2016.1254613. [PubMed] [CrossRef] [Google Scholar]58. Lin J.D., Yang S.F., Wang Y.H., Fang W.F., Lin Y.C., Liou B.C., Lin Y.F., Tang K.T., Cheng C.W. Association of melatonin receptor gene polymorphisms with Graves’ disease. PLoS ONE. 2017;12:e0185529.  doi: 10.1371/journal.pone.0185529. [PMC free article] [PubMed] [CrossRef] [Google Scholar]59. Rauf A., Imran M., Suleria H.A.R., Ahmad B., Peters D.G., Mubarak M.S. A comprehensive review of the health perspectives of resveratrol. Food Funct. 2017;8:4284–4305. doi: 10.1039/C7FO01300K. [PubMed] [CrossRef] [Google Scholar]60. Limmongkon A., Janhom P., Amthong A., Kawpanuk M., Nopprang P., Poohadsuan J., Somboon T., Saijeen S., Surangkul D., Metawee S., et al.  Antioxidant activity, total phenolic, and resveratrol content in five cultivars of peanut sprouts. Asian Pac. J. Trop. Biomed. 2017;7:332–338. doi: 10.1016/j.apjtb.2017.01.002. [CrossRef] [Google Scholar]61. Rauf A., Imran M., Butt M.S., Nadeem M., Peters D.G., Mubarak M.S. Resveratrol as an anti-cancer agent: A review. Crit. Rev. Food Sci. Nutr. 2016 doi: 10.1080/10408398.2016.1263597. [PubMed] [CrossRef] [Google Scholar]62. Aggarwal B.B., Bhardwaj A., Aggarwal R.S., Seeram N.P., Shishodia S., Takada Y. Role of resveratrol in prevention and therapy of cancer: Preclinical and clinical studies. Anticancer Res. 2004;24:2783–2840. [PubMed] [Google Scholar]63. Duntas L.H. Resveratrol and its impact on aging and thyroid function. J. Endocrinol. Investig. 2011;34:788–792. [PubMed] [Google Scholar]64. Yu X.M., Jaskula-Sztul R., Ahmed K., Harrison A.D., Kunnimalaiyaan M., Chen H. differentiation markers expression in anaplastic thyroid carcinoma via activation of Notch2 signaling and suppresses cell growth. Mol. Cancer Ther. 2013;12:1276–1287. doi: 10.1158/1535-7163.MCT-12-0841. [PMC free article] [PubMed] [CrossRef] [Google Scholar]65. Shih A., Davis F.B., Lin H.Y., Davis P.J. Resveratrol induces apoptosis in thyroid cancer cell lines via a MAPK- and p53-dependent mechanism. J. Clin. Endocrinol. Metab. 2002;87:1223–1232. doi: 10.1210/jcem.87.3.8345. [PubMed] [CrossRef] [Google Scholar]66. Truong M., Cook M.R., Pinchot S.N., Kunnimalaiyaan M., Chen H. Resveratrol induces Notch3-mediated apoptosis and suppression of neuroendocrine markers in medullary thyroid cancer. Ann. Surg. Oncol. 2011;18:1506–1511. doi: 10.1245/s10434-010-1488-z. [PMC free article] [PubMed] [CrossRef] [Google Scholar]67. Giuliani C., Iezzi M., Ciolli L., Hysi A., Bucci I., Di Santo S., Rossi C., Zucchelli M., Napolitano G. Resveratrol has anti-thyroid effects both in vitro and in vivo. Food Chem. Toxicol. 2017;107:237–247. doi: 10.1016/j.fct.2017.06.044. [PubMed] [CrossRef] [Google Scholar]68. Sebai H., Hovsepian S., Ristorcelli E., Aouani E., Lombardo D., Fayet G. Resveratrol increases iodide trapping in the rat thyroid cell line FRTL-5. Thyroid. 2010;20:195–203. doi: 10.1089/thy.2009.0171. [PubMed] [CrossRef] [Google Scholar]71. Negro R., Attanasio R., Grimaldi F., Marcocci C., Guglielmi R., Papini E. A 2016 Italian Survey about the Clinical Use of Selenium in Thyroid Disease. Eur. Thyr. J. 2016;5:164–170. doi: 10.1159/000447667. [PMC free article] [PubMed] [CrossRef] [Google Scholar]72. Alexander E.K., Pearce E.N., Brent G.A., Brown R.S., Chen H., Dosiou C., Grobman W.A., Laurberg P., Lazarus J.H., Mandel S.J., et al.  2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum. Thyroid. 2017;27:315–389. doi: 10.1089/thy.2016.0457. [PubMed] [CrossRef] [Google Scholar]73. Drutel A., Archambeaud F., Caron P. Selenium and the thyroid gland: More good news for clinicians. Clin. Endocrinol. (Oxf) 2013;78:155–164. doi: 10.1111/cen.12066. [PubMed] [CrossRef] [Google Scholar]74. Köhrle J. Selenium and the thyroid. Curr. Opin. Endocrinol. Diabetes Obes. 2013;20:441–448. doi: 10.1097/01.med.0000433066.24541.88. [PubMed] [CrossRef] [Google Scholar]75. Derumeaux H., Valeix P., Castetbon K., Bensimon M., Boutron-Ruault M.C., Arnaud J., Hercberg S. Association of selenium with thyroid volume and echostructure in 35- to 60-year-old French adults. Eur. J. Endocrinol. 2003;148:309–315. doi: 10.1530/eje.0.1480309. [PubMed] [CrossRef] [Google Scholar]76. Rasmussen L.B., Schomburg L., Köhrle J., Pedersen I.B., Hollenbach B., Hög A., Ovesen L., Perrild H., Laurberg P. Selenium status, thyroid volume, and multiple nodule formation in an area with mild iodine deficiency. Eur. J. Endocrinol. 2011;164:585–590. doi: 10.1530/EJE-10-1026. [PubMed] [CrossRef] [Google Scholar]77. Burk R.F., Hill K.E. Selenoprotein P: An extracellular protein with unique physical characteristics and a role in selenium homeostasis. Ann. Rev. Nutr. 2005;25:215–235. doi: 10.1146/annurev.nutr.24.012003.132120. [PubMed] [CrossRef] [Google Scholar]78. Burk R.F., Norsworthy B.K., Hill K.E., Motley A.K., Byrne D.W. Effects of chemical form of selenium on plasma biomarkers in a high-dose human supplementation trial. Cancer Epidemiol. Biomarkers Prev. 2006;15:804–810. doi: 10.1158/1055-9965.EPI-05-0950. [PubMed] [CrossRef] [Google Scholar]79. Cui Z., Huang J., Peng Q., Yu D., Wang S., Liang D. Risk assessment for human health in a seleniferous area, Shuang’an, China. Environ. Sci. Pollut. Res. Int. 2017;24:17701–17710. doi: 10.1007/s11356-017-9368-8. [PubMed] [CrossRef] [Google Scholar]80. Dinh Q.T., Cui Z., Huang J., Tran T.A.T., Wang D., Yang W., Zhou F., Wang M., Yu D., Liang D. Selenium distribution in the Chinese environment and its relationship with human health: A review. Environ. Int. 2018;112:294–309. doi: 10.1016/j.envint.2017.12.035. [PubMed] [CrossRef] [Google Scholar]81. Duntas L., Benvenga S. Selenium: An element for life. Endocrine. 2015;48:756–775. doi: 10.1007/s12020-014-0477-6. [PubMed] [CrossRef] [Google Scholar]82. Huang Z., Rose A.H., Hoffmann P.R. The role of selenium in inflammation and immunity: From molecular mechanisms to therapeutic opportunities. Antioxid. Redox Signal. 2012;16:705–743. doi: 10.1089/ars.2011.4145. [PMC free article] [PubMed] [CrossRef] [Google Scholar]83. Toulis K.A., Anastasilakis A.D., Tzellos T.G., Goulis D.G., Kouvelas D. Selenium supplementation in the treatment of Hashimoto’s thyroiditis: A systematic review and a metaanalysis. Thyroid. 2010;20:1163–1173. doi: 10.1089/thy.2009.0351. [PubMed] [CrossRef] [Google Scholar]84. Bülow Pedersen I., Knudsen N., Carlé A., Schomburg L., Köhrle J., Jørgensen T., Rasmussen L.B., Ovesen L., Laurberg P. Serum selenium is low in newly diagnosed Graves’ disease: A population-based study. Clin. Endocrinol. (Oxf) 2013;79:584–590. doi: 10.1111/cen.12185. [PubMed] [CrossRef] [Google Scholar]85. Leo M., Bartalena L., Rotondo Dottore G., Piantanida E., Premoli P., Ionni I., Di Cera M., Masiello E., Sassi L., Tanda M.L. Effects of selenium on short-term control of hyperthyroidism due to Graves’ disease treated with methimazole: Results of a randomized clinical trial. J. Endocrinol. Investig. 2017;40:281–287. doi: 10.1007/s40618-016-0559-9. [PubMed] [CrossRef] [Google Scholar]86. Calissendorff J., Mikulski E., Larsen E.H., Möller M. A Prospective Investigation of Graves’ Disease and Selenium: Thyroid Hormones, Autoantibodies and Self-Rated Symptoms. Eur. Thyroid J. 2015;4:93–98. doi: 10.1159/000381768. [PMC free article] [PubMed] [CrossRef] [Google Scholar]87. Wang L., Wang B., Chen S.R., Hou X., Wang X.F., Zhao S.H., Song J.Q., Wang Y.G. Effect of Selenium Supplementation on Recurrent Hyperthyroidism Caused by Graves’ Disease: A Prospective Pilot Study. Horm. Metab. Res. 2016;48:559–564. doi: 10.1055/s-0042-110491. [PubMed] [CrossRef] [Google Scholar]88. Kahaly G.J., Riedl M., König J., Diana T., Schomburg L. Double-blind, placebo-controlled, randomized trial of selenium in graves hyperthyroidism. J. Clin. Endocrinol. Metab. 2017;102:4333–4341. doi: 10.1210/jc.2017-01736. [PubMed] [CrossRef] [Google Scholar]89. Zheng H., Wei J., Wang L., Wang Q., Zhao J., Chen S., Wei F. Effects of Selenium Supplementation on Graves’ disease: A Systematic Review and Meta-Analysis. Evid. Based Complement. Alternat. Med. 2018;2018:3763565. doi: 10.1155/2018/3763565. [PMC free article] [PubMed] [CrossRef] [Google Scholar]90. Watt T., Cramon P., Bjorner J.B., Bonnema S.J., Feldt-Rasmussen U., Gluud C., Gram J., Hansen J.L., Hegedüs L., Knudsen N. Selenium supplementation for patients with Graves’ hyperthyroidism (the GRASS trial): Study protocol for a randomized controlled trial. Trials. 2013;14:119. doi: 10.1186/1745-6215-14-119. [PMC free article] [PubMed] [CrossRef] [Google Scholar]91. Khong J.J., Goldstein R.F., Sanders K.M., Schneider H., Pope J., Burdon K.P., Craig J.E., Ebeling P.R. Serum selenium status in Graves’ disease with and without orbitopathy: A case-control study. Clin. Endocrinol. (Oxf) 2014;80:905–910. doi: 10.1111/cen.12392. [PubMed] [CrossRef] [Google Scholar]92. Marcocci C., Kahaly G.J., Krassas G.E., Bartalena L., Prummel M., Stahl M., Altea M.A., Nardi M., Pitz S., Boboridis K. European Group on Graves’ Orbitopathy. Selenium and the course of mild Graves’ orbitopathy. N. Engl. J. Med. 2011;364:1920–1931. doi: 10.1056/NEJMoa1012985. [PubMed] [CrossRef] [Google Scholar]93. Gärtner R., Gasnier B.C.H., Dietrich J.W., Krebs B., Angstwurm M.W. Selenium supplementation in patients with autoimmune thyroiditis decreases thyroid peroxidase antibodies concentrations. J. Clin. Endocrinol. Metab. 2002;87:1687–1691. doi: 10.1210/jcem.87.4.8421. [PubMed] [CrossRef] [Google Scholar]94. Duntas L.H., Mantzou E., Koutras D.A. Effects of a six month treatment with selenomethionine in patients with autoimmune thyroiditis. Eur. J. Endocrinol. 2003;148:389–393. doi: 10.1530/eje.0.1480389. [PubMed] [CrossRef] [Google Scholar]95. Turker O., Kumanlioglu K., Karapolat I., Dogan I. Selenium treatment in autoimmune thyroiditis: 9-month follow-up with variable doses. J. Endocrinol. 2006;190:151–156. doi: 10.1677/joe.1.06661. [PubMed] [CrossRef] [Google Scholar]96. Winther K.H., Bonnema S.J., Cold F., Debrabant B., Nybo M., Cold S., Hegedüs L. Does selenium supplementation affect thyroid function? Results from a randomized, controlled, double-blinded trial in a Danish population. Eur. J. Endocrinol. 2015;172:657–667. doi: 10.1530/EJE-15-0069. [PubMed] [CrossRef] [Google Scholar]97. Van Zuuren E.J., Albusta A.Y., Fedorowicz Z., Carter B., Pijl H. Selenium supplementation for Hashimoto’s thyroiditis. Cochrane Database Syst. Rev. 2013;6:CD010223. doi: 10.1002/14651858.CD010223.pub2. [PubMed] [CrossRef] [Google Scholar]98. Winther K.H., Wichman J.E., Bonnema S.J., Hegedüs L. Insufficient documentation for clinical efficacy of selenium supplementation in chronic autoimmune thyroiditis, based on a systematic review and meta-analysis. Endocrine. 2017;55:376–385. doi: 10.1007/s12020-016-1098-z. [PMC free article] [PubMed] [CrossRef] [Google Scholar]99. Winther K.H., Watt T., Bjørner J.B., Cramon P., Feldt-Rasmussen U., Gluud C., Gram J., Groenvold M., Hegedüs L., Knudsen N. The chronic autoimmune thyroiditis quality of life selenium trial (CATALYST): Study protocol for a randomized controlled trial. Trials. 2014;15 doi: 10.1186/1745-6215-15-115. [PMC free article] [PubMed] [CrossRef] [Google Scholar]100. Negro R., Greco G., Mangieri T., Pezzarossa A., Dazzi D., Hassan H. The influence of selenium supplementation on postpartum thyroid status in pregnant women with thyroid peroxidase autoantibodies. J. Clin. Endocrinol. Metab. 2007;92:1263–1268. doi: 10.1210/jc.2006-1821. [PubMed] [CrossRef] [Google Scholar]101. Mao J., Pop V.J., Bath S.C., Vader H.L., Redman C.W., Rayman M.P. Effect of low-dose selenium on thyroid autoimmunity and thyroid function in UK pregnant women with mild-to-moderate iodine deficiency. Eur. J. Nutr. 2016;55:55–61. doi: 10.1007/s00394-014-0822-9. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
OTC Thyroid ‘Boosters’ May Harm
Patients who take over-the-counter supplements that promise to enhance thyroid function may get more than they bargained for, endocrinologists warn.
The supplements could contain unlabeled ingredients, including the active thyroid hormones T3 and T4, which could make patients hyperthyroid, increasing the risk of side effects such as high heart rate, sweating, and anxiety, according to Stephanie Lee, MD, PhD, director of the thyroid health center at Boston Medical Center.
“Over-the-counter thyroid supplements are not supposed to contain any thyroid hormone,” Lee told MedPage Today. “But there’s no truth-in-labeling in these supplements.”
“People who are unsuspecting, or who are already on thyroid medications … can become significantly and severely hyperthyroid,” Lee said.
Lee said thyroid supplements have gained popularity because the symptoms of hypothyroidism  —  especially fatigue and weight gain  —  are so common in normal aging. Women looking for a quick fix to those problems may be attracted to supplements that promise to boost thyroid function.
The problem, Lee said, is that only about 6% to 8% of women are truly hypothyroid and need hormone replacement. When supplements claim to only contain herbs, women may think this can do little harm.
But when those supplements do contain thyroid hormone without saying so on their labeling, and women without genuine thyroid deficiency take them, that’s when problems can arise, Lee said. And it’s not uncommon for these supplements to be mislabeled.
Supplements Use Cow Thyroid
Grace Kang, MD, chief of endocrinology at Landstuhl Regional Medical Center in Germany, and colleagues decided to look into 10 popular thyroid supplements after one of their co-authors saw a patient who developed thyrotoxicosis after taking over-the-counter thyroid supplements.
In a study in Thyroid, they analyzed the biochemical composition of these supplements via liquid chromatography to measure levels of the two main thyroid hormones  —  thyroxine (T4) and triiodothyronine (T3).
They found that nine of the 10 supplements had detectable levels of either thyroid hormone, and when taken at recommended daily doses, could give patients a much bigger kick than clinicians would recommend even for deficient patients.
Nine of the supplements contained T3, ranging from 1.3 mcg to 25.4 mcg per tablet. If patients took those supplements as recommended on the label, they could get as much as 32 mcg per day.
Five of the supplements were found to contain T4, which is essentially levothyroxine (Synthroid), the main medication used by doctors to treat hypothyroidism. The doses ranged from under 0.5 mcg to about 23 mcg, the latter being equivalent to the lowest starting dose of the drug.
If taken per label instructions, patients may be ingesting approximately 92 mcg of T4 per day, Kang and colleagues found.
Even when patients do have clinically diagnosed hypothyroidism, giving the exact needed dose of thyroid hormone is critical, because thyroid drugs are classified by the FDA as having a narrow therapeutic index.
“That means the amount of medication is so important to have just right, that it requires physicians monitor and measure hormone levels,” Lee said.
When patients with normal thyroid levels get this much hormone  —  the kind in supplements usually comes from cows  —  they can develop hyperthyroidism. Lee said patients will feel like they’ve had too much coffee with a bolstered heart rate and feeling shaky, as well as a bit edgy.
And it’s not just excess thyroid hormone that poses a problem for thyroid supplements, Lee said. Some are formulated with high doses of iodine, the main element used by the thyroid to synthesize its hormones.
Often these supplements are made from seaweed, she said, and can contain as much as 800 mcg of iodine per drop, when the standard recommended daily intake is only 150 mcg.
They can also be contaminated with heavy metals, particularly arsenic, Lee said. Seaweed is exposed to these compounds in seawater and when it’s dried out, the arsenic and other contaminants can concentrate.
“It’s dangerous to take these supplements,” Lee said. “You just don’t know what’s in there.”
Supplement Regulations
The $24 billion supplement industry faces little regulation. It’s governed by the 1994 Dietary Supplement Health and Education Act (DSHEA), which exempts these pills from FDA quality assurance tests prior to getting on the market.
But experts say clinicians can pick up that slack.
“My study emphasizes that providers remain alert about patients’ supplement use, and educate patients about the potential adverse effects related to dietary and herbal supplements marketed to aid thyroid function,” Kang said in an email to MedPage Today.
Lee pointed out that clinicians need to be especially vigilant with patients whose thyroid levels are particularly challenging to control.
“You should not only make sure that they’re taking their medication correctly  —  on an empty stomach 30 minutes away from food or coffee, and 2 hours away from iron  —  [but] you really have to ask about supplement use,” Lee said. “It’s clear enough that thyroid hormones in supplements can make someone’s levels abnormal even if they only take one tablet a day.”
 Please enable JavaScript to view the comments powered by Disqus.
Best Thyroid Supplement: 11 Natural Ingredients
Sometimes the best thyroid supplement you’ll ever need is sourced from natural and organic ingredients.
RELATED: 12 Best And Worst Foods For Thyroid Health
Best Thyroid Supplement: 11 Natural Ingredients
1. Iodine
Iodine is probably the best supplement out there because it helps in creating hormones. It can be found in milk, cheese, poultry, seaweed, and iodized salt.
Iodine makes up most of T3 and T4, the two primary hormones that the thyroid gland produces. Without it, metabolic conditions like hypothyroidism may occur.
Other than eating iodine-rich foods, there are two primary iodine supplements: One is a salt called potassium iodide and one by way of chelated iodine.
Potassium iodide should be taken with caution, as the body has the tendency to absorb it rapidly. Make sure you don’t take too much of it, and always consult with your doctor to find out what daily amount works best.
Chelated iodine comes from seaweed-based foods like kelp. Unlike potassium iodide, it takes much longer for the body to absorb it. This ensures a steady iodine release for your thyroid to use.
Note: Taking iodine supplements with high blood pressure medication and/or diuretics may increase the risk of high blood potassium.
What Is T3? T3 is triiodothyronine, a thyroid hormone that affects development, growth, body temperature, and metabolism. It is the active form of thyroxine.
What Is T4? T4 is thyroxine, the main hormone that the thyroid gland produces and secretes into the bloodstream.
2. Vitamin B12
This is another thyroid supplement that is also conveniently water-soluble. Vitamin B12 is crucial in assisting with cell metabolism, as well as nerve cell function, and reducing the dreaded brain fog.
Studies show that vitamin B12 deficiency is common in those suffering from hypothyroidism. This is due to hypothyroidism impairing your body’s ability to effectively absorb vitamin B12.
While increasing your intake of vitamin B12 rich foods like clams, sardines, and animal liver and kidneys seems ideal, taking supplements is highly recommended. This is due to their solubility in water, making them better and more quickly absorbed by the body than dietary B12.
3. Selenium
Selenium is another important supplement necessary for thyroid health. It helps with building the enzymes necessary to convert T4 toT3.
Selenium also helps out the thyroid gland by reducing inflammation and removing harmful substances.
The human body doesn’t produce selenium naturally, which is why partaking in selenium-rich foods like Brazil nuts, eggs, and dairy products is important. Opting for the best selenium thyroid supplements works as well.
Take note that overconsumption of selenium can cause complications with anxiety and sleep. The recommended daily dose for selenium is 55 micrograms.
4. Zinc
Zinc plays a vital role in thyroid function, as it lets T3 receptors bind to the hormone T3. When you don’t have enough zinc present, your body won’t be able to absorb T3 introduced into your body via diet and/or medications.
Zinc is also responsible for helping out with testosterone production, wound healing, and increasing insulin sensitivity. Foods rich in zinc include shellfish, legumes, seeds, nuts, whole grain, and dairy.
Zinc should also not be taken at the same time as certain antibiotics (Sumycin, Cipro, and Achromycin), as it will decrease the efficacy of both medications. You can remedy this by taking the antibiotics either 2 hours before taking your zinc supplements, or about 4-6 hours afterward.
5. Magnesium
Magnesium has a two-way function for your thyroid: first, it helps in the conversion of T4 to T3. It also helps boost T4 production, while preventing overproduction at the same time.
Magnesium also evens out blood sugar levels, promotes, bone development, and supports protein synthesis. It’s also well known as an aid for those having problems with sleeping.
6. Copper
Copper is an important micronutrient that helps to regulate levels of T3 in the body. A deficiency in copper can lead to inhibition in T4-T3 conversion, which in turn leads to an excess of T4 hormones in the bloodstream.
Copper works hand in hand with zinc in regulating the activities of the thyroid gland. They are often found together in the best thyroid support supplement in stores available for hypothyroidism, for example.
Foods that are rich in copper include liver, sweet potatoes, and oysters. To be able to achieve optimum copper and zinc teamwork, you should also avoid foods that deplete your body’s zinc levels, like refined carbs and alcohol.
RELATED: Vitamin D2 Vs D3: What Are The Similarities And Differences?
7. Molybdenum
Molybdenum is a mineral that is usually present in the body that can be easily sourced and efficiently retained. It is also important for the production of energy and improving sleep quality.
Molybdenum has two functions in thyroid support: sufficient levels inhibit the buildup of fluoride in the thyroid gland, which can otherwise lead to thyroid toxicity. It also manufactures enzymes that release T3 hormones from the thyroid gland storage.
Foods that are rich in molybdenum include peas, lentils, nuts, whole grains, and eggs.
8. Manganese
Manganese is best known as a mineral that can help repair bones and maintain a healthy immune system. It is important for the thyroid system in two ways:
First, it helps transport T4 into the cells.
Second, it helps in protecting the thyroid gland from getting stressed out and worn down.
If you decide to opt for dietary manganese instead of supplements, manganese-rich foods include legumes, meats, nuts, and fish. Leafy greens are also a good option for manganese content, but look out for their iron content which could inhibit the body’s absorption of manganese.
9. L-Tyrosine
This is a type of amino acid that helps in the production of many hormones in your body. It also helps build neurotransmitters like dopamine, that famous feel-good brain chemical that does wonders for your mood.
L-tyrosine is also important for T3 and T4 production, making it a crucial part of supporting thyroid health. A deficiency in this amino acid could lead to lowered T3 and T4 production, which in turn can lead to hypothyroidism.
Adapting your diet is the best way to up your intake of L-tyrosine. Foods that are high in L-tyrosine include chicken, beef, green vegetables, and dairy products.
The best thyroid supplements also include L-tyrosine, and there are also several supplements in powder, capsule, and tablet form. But take note that taking l-tyrosine is only greenlit for those who have normal iodine levels, as it will only work when combined with this mineral.
10. Vitamin D
Vitamin D deficiency has strong links to hypothyroidism, and studies have shown that an increase of Vitamin D intake improved the TSH levels in patients with hypothyroidism.
Foods rich in Vitamin D include fortified dairy products like milk and yogurt, as well as orange juice. But dietary vitamin D may not be enough, and vitamin D supplements may be recommended by your doctor upon consultation.
Taken, orally, vitamin D supplements also provide a better source besides unprotected sun exposure. Though it is always best to ask your doctor if vitamin D can be taken in tandem with your specific thyroid medication.
What Is TSH? TSH is Thyroid Stimulating Hormone, also known as thyrotropin. It is produced by the pituitary gland and stimulates the receptors of thyroid cells, which prods them into producing T3 and T4.
11. Capsaicin
This is the substance responsible for making chili peppers so notoriously spicy. It surprisingly plays a role in treating hypothyroidism by helping to restore regular thyroid hormone production.
Capsaicin also helps alleviate symptoms brought about by hypothyroidism such as pain and poor blood circulation. Cayenne pepper is a choice spice that can be added to foods to reap the benefits of capsaicin, but if you’re not a lover of spice then capsaicin pill supplements are ideal.
Capsaicin in pill form appears in stores as cayenne pepper supplements. Consult your doctor when taking capsaicin pills, as they are known to lower blood sugar levels; you’d want to avoid this side effect as much as you’d want to avoid diabetes as it could cause lightheadedness and feeling of weakness.
 
Check out this video from Palak Notes for some of the best thyroid supplements:

The best thyroid supplements are safe and natural, like the ones listed above. Not only will they promote good thyroid health, but also cause improvements in energy levels, moods, and metabolism.
Always make sure to consult with your doctor before partaking in any dietary or medicinal supplement. You should also be sure to take your supplements when your immune system is at its most active, which is usually in the early morning.
What kind of supplement has done wonders for your thyroid health? Share them with us in the comments section below! 
Up Next: 
 Vitamins and microelements involved in the regulation of the thyroid gland function (I, Se, Mg, Cu, vitamin B6) 
 A study that allows you to control the level of vitamins and microelements, with the help of which the normal functioning of the thyroid gland is carried out.
  Russian synonyms 
 Iodine; selenium; magnesium; copper; vitamin B6 (pyrodixin).
  Synonyms     English 
 Iodine; Selenium; Magnesium; Copper; Vitamin B6, Pyroxine.
  Research method 
 High performance liquid chromatography.
  Which biomaterial can be used for research? 
 Venous blood.
  How to properly prepare for the study? 
 Do not eat for 2-3 hours before the test, you can drink clean still water.
 Do not smoke within 30 minutes prior to examination.
  General information about the study 
   Iodine   – a trace element that is completely absorbed in the stomach and duodenum, almost completely absorbed from the blood by the thyroid gland and kidneys.The average daily intake of iodine by the thyroid gland of an adult is about 60-95 mcg. The physiological role of iodine in the human body is participation in the synthesis of thyroid hormones of the thyroid gland. Iodine deficiency during pregnancy and infancy can lead to neurological and psychological deficits in children. The IQ is lower in children in areas with significant iodine deficiency than in children living in areas with sufficient iodine. Iodine deficiency remains one of the leading causes of mental retardation in the world.In adults, mild iodine deficiency increases the incidence of hyperthyroidism due to toxic goiter. Excessive iodine intake can affect thyroid function, but most people tolerate high doses of dietary iodine fairly well. When exposed to very high doses of iodine, the synthesis of thyroid hormones decreases. People with autoimmune thyroid disease often develop hypothyroidism within a few weeks after exposure to high doses of iodine. The dramatic increase in iodine intake in iodine-deficient regions can also cause autoimmune thyroid disease.
 In the human body, the thyroid gland is an organ with a high content of   selenium   (Se). Selenoproteins play an important role in cellular defense against free radicals and highly reactive oxygen species. In addition, the content of selenium directly affects the activity of deiodinase enzymes, therefore, it is involved in the production of thyroid hormones. Severe selenium deficiency can cause thyroid dysfunction and lead to the onset or progression of autoimmune diseases.In patients with Hashimoto’s thyroiditis, supplementation with selenium supplementation may reduce thyroid peroxidase antibody titer.
 Less effect on the thyroid gland is exerted by   magnesium  . A decrease in the content of magnesium in the blood is described in thyrotoxicosis. Elevated blood levels of magnesium have been reported in patients with elevated thyroid-stimulating hormone levels. However, the mechanisms of changes in magnesium metabolism in thyroid pathology are not fully understood.
   Copper   participates in redox reactions, is one of the important elements of the body’s antioxidant defense.The lack of this trace element affects the endocrine system, including the thyroid gland. The balance of trace elements zinc / copper is especially important, in violation of which the hormonal function of the gland can be disrupted.
   Vitamin B6   is a coenzyme involved in more than 100 enzymatic reactions in the human body. It is required for the production of neurotransmitters, myelin sheaths, hemoglobin, myoglobin, and homocitesteine ​​metabolism. Deficiency of vitamin B6 can lead to hypothyroidism caused by a decrease in the synthesis of thyroid-stimulating hormone in the hypothalamus.An excess of B6 can lead to a decrease in thyroid-stimulating hormone.
  What is the research used for? 
 To control the balance of trace elements and the concentration of vitamin B6 in diseases of the thyroid gland.
  When is the study scheduled? 
 For complex diagnostics in patients with newly diagnosed thyroid diseases.
 For preventive examinations of patients with thyroid diseases.
  What do the results mean? 
 Reference values ​​
  Iodine: 30 – 60 μg / L 
  Selenium: 23 – 190 μg / L 
  Magnesium: 12.15 – 31.59 mg / l 
  Copper: 575 – 1725 μg / L 
  Vitamin   B   6: 8.7 – 27.2 ng  /  ml 
 The results of a multicomponent study of microelements and vitamins involved in the regulation of the thyroid gland are evaluated by the attending physician taking into account the pathology, anamnesis, clinic and the results of other examination methods.
 Diet / foods associated with thyroid cancer risk 
 Highlights 
 Various studies and meta-analyzes have shown that consuming natural foods and supplements such as fruits, vegetables, milk and dairy products, seafood, and moderate amounts of genistein may be beneficial in reducing the risk of thyroid cancer and possibly alleviating symptoms. and support the treatment of this cancer. However, relatively low and extremely high dietary iodine intakes, starchy and sugary foods, and obesity-causing foods should be avoided as these can increase the risk of thyroid cancer.Therefore, following a personalized diet / meal plan with the right foods and supplements and staying physically active are essential when it comes to treating and preventing thyroid cancer.
 Thyroid cancer incidence 
 Thyroid cancer is a type of cancer that affects the thyroid gland, a small butterfly-shaped gland located at the base of the neck. Thyroid cancer is also one of the most common endocrine cancers.According to the American Cancer Society, around 2021 new cases of thyroid cancer could be diagnosed in the year 44,280.
 Thyroid cancer is commonly seen in people aged 30 and over, but it can develop at any age. Women are more likely to develop this cancer than men. Exposure to radiation on the head or neck is one of the common risk factors for thyroid cancer.
 The four types of thyroid cancer include:
  Papillary thyroid cancer  – found in 80% of thyroid cancer cases; grows slowly, but can spread to lymph nodes in the neck.
  Follicular thyroid carcinoma  – the second most common thyroid cancer; Hertle cell cancer is a rare and more aggressive type of follicular thyroid cancer.
  Medullary cancer  – a rare type of thyroid cancer; lymph node spread / metastasis is common at the time of diagnosis
  Anaplastic thyroid cancer  – Least common thyroid cancer; tumors grow rapidly and spread to other parts of the body; most difficult to treat
 Foods to Eat After Cancer Diagnosis!
 No two cancers are the same.Go beyond general dietary guidelines for everyone and make individual decisions about food and supplements with confidence.
 Symptoms of thyroid cancer 
 In the early stages of thyroid cancer, there may be no signs or symptoms. However, as the disease progresses, it can lead to many symptoms of cancer, including:
 A lump (nodule) on the neck that can grow rapidly
 Increased hoarseness and other changes in voice
 Difficulty breathing
 Difficulty swallowing
 Persistent cough – not due to a cold
 Sore throat and neck, extending to the ears
 Painless swelling in the neck
 Many of these symptoms can also occur with other non-cancerous diseases and are not necessarily associated with thyroid cancer.However, if you experience any signs or symptoms associated with throat cancer, see your doctor immediately.
 Treatment options for thyroid cancer 
 The decision to treat thyroid cancer depends on various factors, including the type of cancer, the extent or stage of the cancer, the patient’s overall health, and medical history. In many cases, thyroid cancer can be cured.
 People with thyroid cancer may need to undergo surgery to remove the thyroid gland, after which they are often treated with hormone therapy.Radioactive iodine treatment is also often used after removal of the thyroid gland to destroy any remaining thyroid tissue that was not removed during surgery. Other treatments for thyroid cancer include radiation therapy, chemotherapy, targeted drug therapy, and supportive (palliative) care. Regardless of the treatment used by patients, good nutrition (with natural products / supplements) is important to help them gain strength and cope with the effects of cancer and treatment.
 Associations of various foods and lifestyle factors with thyroid cancer risk 
 When it comes to caring for, treating or preventing any cancer, including thyroid cancer, individualized diet / nutritional intake, including natural foods and nutritional supplements, and a healthy lifestyle are critical. Below are a few examples of studies that have assessed the relationship of various foods and lifestyle factors to thyroid cancer risk.
 Relatively low and extremely high intake of dietary iodine may increase the risk of thyroid cancer 
 Researchers from the Sunchonghyang University College of Medicine and the Sungyunkwan University School of Medicine in Korea analyzed urinary iodine concentration (UIC) data from 1,170 thyroid nodules and found that a relatively low iodine intake, corresponding to a UIC of <300 μg / L, and extremely excessive An iodine intake corresponding to a UIC ≥ 2500 mcg / L may increase the risk of thyroid cancer in iodine-rich areas in Korea.(Hye Jung Kim et al., Eur J Nutr., 2017)
 Another study by researchers from the College of Medicine of Songchunhyang University and the School of Medicine of Sungyunkwan University in Korea also showed that relatively low iodine intake corresponding to UIC <300 μg / L and more than excessive iodine intake corresponding to UIC ≥ 500 μg / L may also increase the risk of BRAF mutations in the thyroid gland, which can lead to the development of papillary thyroid cancer.(Hye Jung Kim et al., Eur J Nutr., 2018)
 Eating starchy and sugary foods may increase the risk of thyroid cancer 
 Researchers at the Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy analyzed data from a case-control study conducted in Italy between 1986 and 1992, involving 399 thyroid cancers and 616 control groups, and found that starchy and sweet foods high glycemic index and glycemic load (a measure of the potential for elevated blood sugar) can increase the risk of thyroid cancer.(J. Randy et al., Ann Oncol., 2008)
 Eating vegetables, dairy products and seafood can reduce the risk of thyroid cancer 
 In a study at a hospital in Sicily, Southern Italy, researchers from the University of Catania analyzed nutritional information for 106 thyroid cancer patients and 217 control patients recruited at the G. Rodolico University Hospital in Catania, and concluded that dietary limited amounts of starchy foods and foods rich in salt, fat and sugar, and a higher intake of cruciferous / non-cruciferous vegetables, milk and dairy products and seafood along with 1 to 2 liters of water per day may help reduce the risk of thyroid cancer.(Maria Fiore et al., Food Chem Toxicol., 2020)
 Another study by researchers from the Yale School of Public Health in New Haven and the Miami Cancer Institute in the United States, and the Beijing Medical College Hospital in Beijing, Sichuan University and Metropolitan Medical University, Beijing, China, also found that those who followed the diet rich in fruits and vegetables, reduced the risk of thyroid cancer, especially among women aged 50 and over. They also found that the risk of thyroid cancer is increased in men who consume a lot of starchy foods and desserts.(Jiaxin Liang et al., Am J Transl Res., 2020)
 These studies show that consuming vegetables, dairy products and seafood can help prevent thyroid cancer. In addition, we must avoid excessive consumption of starchy foods and desserts to reduce the risk of thyroid cancer.
 Are cruciferous vegetables good for cancer? | Proven Individual Diet
 Watch this video on YouTube
 Taking moderate amounts of genistein may reduce the risk of thyroid cancer in women 
 Researchers from Icahn School of Medicine at Mount Sinai in New York, Yale University in Connecticut, Miami Cancer Institute in Florida, Chinese Academy of Medical Sciences, and Metropolitan Medical University in China analyzed data from a 2010 population-based study in Connecticut.to 2011, including 387 thyroid cancers and 433 control populations, and found that moderate intake of genistein can reduce the risk of papillary macrocarcinomas of the thyroid gland with tumors> 1 cm in diameter in women. (Qian Wang et al., Biomarker Excess in Cancer Epidemiology, 2020)
 Overweight and obese adolescents may increase the risk of papillary thyroid cancer in adulthood 
 Researchers at Seoul National University and Ewha Women’s University College of Medicine in Seoul, Korea analyzed data from a case-control study conducted in the Republic of Korea with 1,549 patients with papillary thyroid cancer and 15,490 people in the control group, and found that overweight and adolescent obesity were associated with a higher risk of papillary thyroid cancer in adulthood.(Kyung-Nam Kim et al., Science Representative, 2020)
 Therefore, avoid excessive consumption of foods that cause obesity, such as red and processed meats, fried foods, processed foods and other instant foods, to reduce the risk of thyroid cancer.
 Link between alcohol and thyroid cancer risk 
 Researchers at Shinhan University in Wuichjongbu and the National Cancer Center in Goyang, Korea conducted a meta-analysis of 3 observational studies, 20 case-control studies, and 11 population-based studies, involving a total of 7,725 thyroid cancer patients and 3,113,679 participants without treatment.Thyroid cancer, obtained through a search of the Pubmed and Embase databases, and found that unlike most other types of cancer, alcohol consumption reduced the risk of thyroid cancer. (Seung-Hee Hong et al, Cancer Res Treat. 2017)
 Conclusion 
 Various observational studies and meta-analyzes show that following a diet / meal plan that contains natural foods such as fruits, vegetables, milk and dairy products, seafood, and moderate amounts of genistein can be beneficial in reducing risk and may even relieve symptoms and support treatment for thyroid cancer.Also avoid relatively low and extremely high iodine intakes, starchy and sugary foods with a high glycemic index, and foods that can cause obesity such as red and processed meats as part of your diet / meal plan as this increases your risk of thyroid cancer … … Eating well (from natural foods and supplements) and maintaining physical activity are essential when it comes to thyroid cancer treatment (with or without treatment) and prevention.
 What food you eat and what supplements you take is your decision. Your decision should include consideration of cancer gene mutations, type of cancer, ongoing treatments and supplements, any allergies, lifestyle information, weight, height, and habits.
 Nutrition planning for cancer from the add-on is not based on Internet searches. It automates the molecular science decision-making process implemented by our scientists and software developers. Whether you want to understand the underlying biochemical molecular pathways or not, this understanding is essential for cancer nutrition planning.
 Get started NOW with meal planning by answering questions about cancer name, genetic mutations, current treatments and supplements, any allergies, habits, lifestyle, age group and gender.
 Foods to Eat After Cancer Diagnosis!
 No two cancers are the same. Go beyond general dietary guidelines for everyone and make individual decisions about food and supplements with confidence.
   Cancer patients often have to deal with various side effects of chemotherapy that affect their quality of life and seek alternative cancer treatments.Taking the right diet and science-based supplements (avoiding guesswork and random selection) is the best natural remedy for cancer and treatment-related side effects.  
 90,000 Thyroid diseases and pregnancy
 In recent years, the prevalence of thyroid gland (thyroid) diseases in pregnant women has been growing, which undoubtedly determines the state of the physical and mental health of the younger generation. The constantly deteriorating environmental and radiation situation contributes to an increase in the incidence of thyroid diseases.
 The main function of thyroid hormones in adults is to maintain basic metabolism in the human body. And at the stage of intrauterine development – the differentiation of tissues, primarily of the nervous, cardiovascular and musculoskeletal systems. Under the influence of these hormones, the development of brain structures occurs, the formation and maintenance of intelligence throughout life. With their lack, the development of the nervous system and the growth of bones slows down.
 The size of the thyroid gland during pregnancy normally increases in each woman by an average of 16% due to a more intensive blood supply to the thyroid tissue and an increase in its mass.
 Changes in the thyroid gland in women occur already from the first weeks of pregnancy, mainly in the 1st half, i.e. during the period when the fetus does not yet have its own gland functioning, and its development depends entirely on the production of the mother’s thyroid hormones.
   Endemic diffuse goiter    –  a disease that occurs in some geographical areas with insufficient iodine content in the environment (which includes the Trans-Baikal Territory) and is characterized by an enlargement of the thyroid gland.Goiter develops in response to prolonged iodine deficiency. Patients are worried about general weakness, increased fatigue, headaches, and discomfort in the region of the heart.
 Iodine deficiency causes impaired reproductive function in women: the number of miscarriages, stillbirths increases, and infant mortality increases. The course of pregnancy and childbirth in women with endemic goiter is accompanied by the frequency of complications such as gestosis (7.2%), chronic intrauterine fetal hypoxia (34%), discoordination of labor (31%), placental insufficiency (18%), threat of termination of pregnancy (18%), etc.
 Insufficient intake of iodine during pregnancy has a negative effect on the fetal thyroid gland and, in the future, the activity of the fetal thyroid gland completely depends only on the intake of iodine from the maternal body, and sometimes leads to the development of goiter.
 The most effective method recommended by the World Health Organization and other international organizations is mass iodine prophylaxis, which consists in the use of edible iodized salt.
 At the stage of pregnancy planning, it is advisable for women to prescribe individual iodine prophylaxis with physiological doses of iodine – Iodomarin 200. For individual iodine prophylaxis in pregnant women, it is necessary to avoid the use of iodine-containing dietary supplements. In any case, a doctor’s consultation is necessary.
 The presence of euthyroid goiter in the patient, for which she is already receiving therapy, is not a contraindication for planning pregnancy, but the main condition for this is reliable maintenance of euthyroidism.During pregnancy every 8 weeks it is necessary to check the level of thyroid hormones in the laboratory.
   Nodular goiter   spreads among 4% of pregnant women and is not a contraindication for planning pregnancy, with the exception of large nodules (more than 4 cm), as well as its termination. It should be noted that, contrary to some beliefs, during pregnancy, the risk of enlargement of nodules is not so great. Like most pregnant women, patients are shown individual iodine prophylaxis with physiological doses of iodine.In any case, monitoring of thyroid function is shown with the determination of the level of hormones in each trimester of pregnancy.
 All women with thyroid diseases should consult an endocrinologist.
  We wish you and your children good health! 
 90,000 Uncontrolled intake of iodine can harm no less radiation – doctors
 In turn, endocrinologist Anna Tselikovskaya said that a person, depending on age and indications, needs from 100 to 200 micrograms of iodine per day.
 “The iodine that is in the tableted medicinal preparations in the form of potassium iodide is microdoses that are physiological for us. Medical iodine, Lugol or ordinary alcohol solution contains grams of iodine. And any person, having dropped, for example, as grandmothers did it before , a drop of iodine on sugar or a piece of bread, will receive grams of iodine dose and provoke a disease. This iodine dose is several times higher than the physiological one. Therefore, it is categorically impossible to consume it in this form, “Tselikovskaya said.
 As for potassium iodide, which is part of many medicinal iodine-containing preparations, there are strict indications that the doctor determines at a personal appointment. “If we exclude the autoimmune nature of the disease of the gland, and understand that the thyroid gland is enlarged against the background of iodine deficiency, we recommend these drugs. We also recommend it to pregnant and lactating women, since they have a greater load on the thyroid gland,” she said.
 According to the doctor, if a person takes iodine uncontrollably, not knowing the state of his thyroid gland, he can provoke a disease – thyrotoxicosis, which is expressed in an increase in the function of the thyroid gland.”Nobody initially checks, does not take tests for hormones. They start taking pills and that’s it,” Tselikovskaya said.
 She added that in some conditions, especially in old age, when people have problems with the thyroid gland in the form of multinodular formations, iodine is generally contraindicated. “Their glands can work actively, and iodine will further provoke thyrotoxicosis,” the doctor said.
 Endocrinologist Ekaterina Aleksandrova agreed with her colleague that an alcoholic solution of pharmaceutical iodine is very difficult to dose, since one drop contains mega-doses.
 “Lugol’s solution also contains iodine. They only rinse their throats, and then we, endocrinologists, prohibit its use by patients who have a history of thyroid disease or relatives,” said Aleksandrova. It is better to consult about taking medicinal iodine-containing preparations, the doctor must say that they are not contraindicated for a person, she added.
 Tselikovskaya and Aleksandrova are sure that potassium iodide should be used only in extreme cases.”I do not know in what quantities potassium iodide is used in nuclear power plants, but I think that, in any case, it is not more than 500-600 micrograms per day. This is a large daily norm for some kind of emergency,” Alexandrova said. …
 As an iodine prophylaxis in a normal situation, Tselikovskaya recommended adding iodized salt and seafood, as well as seaweed, to the daily diet. Alexandrova added that using these products to protect the thyroid gland from increased radiation will not work.”In seaweed, less iodine is contained, it is difficult to dose. Seaweed needs to be eaten in kilograms. Who will eat it in such quantity and what’s the point?” She said.
 “If we still talk about how to protect the thyroid gland from radiation, we must saturate our gland with iodine so that it does not” grab “radioactive iodine. time to take medicinal iodine-containing preparations is painless, “Alexandrova concluded.
 About thyroid gland surgery 
 This guide will help you prepare for thyroid surgery at Memorial Sloan Kettering (MSK). It will also help you understand what to expect as you recover.
 Use this manual as a reference as you prepare for the day of surgery. Always take it with you to MSK, including on the day of your surgery. You and your healthcare team will guide you through your treatment.
 to come back to the beginning
 Operation Information 
 Thyroid Information 
  The thyroid gland  is a small butterfly-shaped gland located in the lower front of the neck (see picture).picture 1). It produces hormones that control how the body converts oxygen and calories into energy. The thyroid gland consists of the left and right lobes. The junction of the two lobes is called the isthmus.
  The parathyroid glands  are 4 small endocrine glands located behind the thyroid gland. They produce a hormone that helps control blood calcium levels.
  Lymph nodes  are small oval or round structures that are found throughout the body.Lymph nodes are part of the immune system. They produce and store cells to fight infection. In addition, the lymph nodes filter bacteria, viruses, cancer cells and other metabolic products from the lymphatic fluid.
 Figure 1. Thyroid gland
 Removal of the thyroid gland 
 Thyroid surgery is performed through an incision (surgical incision) in the lower front of the neck.It lasts about 2-3 hours.
 During the operation, the surgeon will examine the entire thyroid gland and remove those parts in which cancer is found. He will also examine the lymph nodes near the thyroid gland and remove any that have or may have cancer cells.
 Surgery to remove half (1 lobe) of the thyroid gland is called lobectomy or hemithyroidectomy.
 An operation to remove the entire thyroid gland is called total thyroidectomy.
 The surgeon will talk with you about what to expect before surgery.
 Nerve damage 
 Near the thyroid gland there are 2 nerves that help the larynx (pharynx) work. These nerves are called the recurrent laryngeal nerve and superior laryngeal nerve. They can be affected during thyroid surgery.
  The recurrent laryngeal nerve  is located behind the thyroid gland and goes into the pharynx. If a tumor is close to this nerve, or if this nerve is damaged during surgery, the vocal cords (2 elastic bands of tissue in the throat that help you speak) may be damaged.This can make you hoarse. Hoarseness is normal after thyroid surgery and usually goes away with time.
  Superior laryngeal nerve  helps to enhance the sonority and tone of your voice. If this nerve becomes weakened or damaged, it can affect the pitch and tone of your voice. This can make it difficult for you to raise your voice or sing.
 Before thyroid surgery, your doctor will check how your vocal cords are working.If they work normally, but the tumor is large or located close to the recurrent or superior laryngeal nerve, the risk of nerve damage during surgery is higher. Although rare, it can lead to problems with the vocal cords after surgery.
 If your voice changes and does not recover after surgery, you may need to undergo a throat exam. There are several ways to improve your voice when nerves are damaged, including surgery or injection (injection) into the vocal cord.You may also need to see a laryngologist (doctor who specializes in voice problems). Your healthcare provider will discuss your options with you.
 In rare cases, nerve damage can lead to breathing problems. In this case, call a healthcare professional who can help you. If you can’t get through right away, go to the nearest emergency room.
 Hypocalcemia (low blood calcium) 
 After surgery, you may experience temporary parathyroid dysfunction.This means that the parathyroid glands may not produce enough hormone to maintain blood calcium levels. Although this is temporary, it can cause hypocalcemia. Hypocalcemia is a condition in which there is not enough calcium in the blood.
 Hypocalcemia can cause numbness or tingling sensation in the hands, feet, and around the mouth. Call your healthcare provider right away if you have any of the symptoms listed below. Severely low blood calcium levels can be dangerous.
 Your health care provider will monitor your blood calcium levels after surgery. If you are diagnosed with hypocalcemia, you will be given medication to correct it. For more information, see the sections “Managing Hypocalcemia” and “Taking Calcium Supplements.”
 to come back to the beginning
 Before surgery 
 The information in this section will help you prepare for your surgery. Read this section after you have assigned your surgery and refer to it as the date of your surgery approaches.It contains important information about what you need to do before your surgery.
 As you read this section, write down the questions you want to ask your healthcare provider.
 Preparation for surgery 
 You and your healthcare team will prepare for your surgery together.
 Help us make your transaction as secure as possible by telling us if any of the statements below match your situation, even if you’re not entirely sure.
 I am taking a blood thinner, for example:
 aspirin;
 Heparin
 Warfarin (Jantoven ®  or Coumadin ® )
 Clopidogrel (Plavix  ® )
 Enoxaparin (Lovenox  ® )
 Dabigatran (Pradaxa  ® )
 Apixaban (Eliquis  ® )
 Rivaroxaban (Xarelto  ® )
There are other similar medications, so be sure to tell your healthcare provider about any medications you are taking.
 I am taking prescription drugs (prescribed by my healthcare provider), including patches and ointments.
 I take over-the-counter medicines (which I buy without a prescription), including patches and ointments.
 I am taking nutritional supplements such as herbs, vitamins, minerals, and natural or home remedies.
 I have a pacemaker, automatic implantable cardioverter defibrillator (AICD), or other cardiac pacemaker.
 I have sleep apnea.
 I used to have problems with anesthesia (with a medication that makes me fall asleep during surgery).
 I am allergic to some drugs or materials such as latex.
 I don’t want to have a blood transfusion.
 I drink alcohol.
 I smoke or use electronic smoking devices (eg disposable e-cigarettes, vape, Juul ® ).
 I take soft drugs.
 On alcohol use 
 The amount of alcohol you drink may affect your condition during and after surgery. It is very important to tell healthcare providers how much alcohol you are drinking. This will help us plan your treatment.
 If you stop drinking abruptly, it can cause seizures, alcoholic delirium and death.
 If we know that you are at risk of these complications, we can prescribe medications for you to avoid them.
 If you drink alcohol regularly, there is a risk of other complications during and after surgery. These include bleeding, infections, heart problems, and longer hospital care.
 To prevent possible problems, before the operation, you can:
 Tell healthcare providers honestly how much alcohol you drink.
 After the appointment of the operation, try to stop drinking alcohol.If, after stopping alcoholic beverages, you experience headaches, nausea (vomiting sensation), increased anxiety, or have trouble sleeping, tell your healthcare provider right away. These are early signs of alcohol withdrawal that can be treated.
 Tell your healthcare provider if you are unable to stop drinking.
 Ask your healthcare provider questions about how drinking alcohol might affect your body in connection with surgery.As always, we will ensure the confidentiality of all your medical information.
 On smoking 
 During surgery, smokers may experience breathing problems. Quitting smoking even a few days before surgery will help prevent these problems. If you smoke, your healthcare provider will refer you to the Tobacco Treatment Program. You can also contact this program by calling 212-610-0507.
 Sleep Apnea Information 
 Sleep apnea is a common breathing disorder that causes a person to stop breathing for a short period during sleep.The most common type is obstructive sleep apnea (OSA). In OSA, the airways are completely blocked during sleep. OSA can cause serious complications during and after surgery.
 Let us know if you have sleep apnea attacks, or if you suspect you may have such attacks. If you are using a breathing apparatus (such as a CPAP machine) to prevent sleep apnea, take it with you on the day of surgery.
 Using MyMSK 
 MyMSK (my.mskcc.org) is your MSK Patient Portal account. You can use MyMSK to communicate with your healthcare team, send and receive messages, view test results, check the date and time of visits, and more. You can also ask your caregiver to create an account to see information about your care.
 If you do not already have a MyMSK account, you can visit the my.mskcc.org, call 646-227-2593 or your doctor’s office to obtain your registration ID. You can also watch the video How to Enroll in MyMSK: Memorial Sloan Kettering’s Patient Portal. Please contact the MyMSK Help Desk at [email protected] or 800-248-0593 for assistance.
 Within 30 days prior to surgery 
 Preoperative study 
 Before your surgery, you will be assigned a presurgical testing (PST).The date, time and location will be indicated in the appointment reminder that you receive at the surgeon’s office. You will help us if you take with you to the preoperative examination:
 A list of all the medicines you take, including prescription and over-the-counter medicines, patches, and creams.
90,037 Results of any tests you did outside of MSK, such as exercise ECG, echocardiogram, or carotid Doppler
90,037 names and phone numbers of the medical staff treating you.
 On the day of your appointment, you can take your food and medicine as usual.
 During the preoperative study, you will meet a highly qualified nurse. This is a medical professional who works with anesthesiologists (medical personnel who have received special training who will perform anesthesia during surgery). A senior nurse / nurse will review your medical record and your surgical history with you. You will need to undergo a number of tests, including an electrocardiogram (EKG) to check your heart rate, chest x-rays, blood tests, and other tests needed to plan your treatment.In addition, a trained nurse can refer you to other specialists.
 The Nurse / Nurse will also tell you which medications you will need to take on the morning of your surgery.
 Determine who will look after you 
 Your caregiver plays an important role in your treatment. Before your surgery, your healthcare team will tell you and your caregiver about the surgery. In addition, the person will need to take you home after your surgery and discharge from the hospital.Also, this person will help you at home.
 Information for caregivers 
 Existing materials and support are available to help you meet the many responsibilities that come with caring for someone undergoing cancer treatment. For support resources and information, visit www.mskcc.org/caregivers or read the resource Guide for Caregivers
 …
 Complete the Health Care Proxy Form 
 If you have not yet completed the Health Care Proxy, we recommend that you do so now.If you have already completed this form or have other advance directives, please take them with you to your next appointment.
 The Power of Attorney for Health Care Decisions is a legal document that specifies the person who will represent you in the event that you are unable to do so on your own. The person listed there will be your health care agent.
 Talk to your healthcare provider if you are interested in completing a Health Care Proxy.You can also read the resources Advance Care Planning and How to Be a Care Representative for information about health care proxies, other advance directives, and acting as a care agent.
 Perform breathing and coughing exercises 
 Take deep breaths and clear your throat before surgery. Your healthcare provider will give you a stimulation spirometer to help expand your lungs.For more information, see the resource How to use your incentive spirometer. If you have any questions, talk to your nurse or pulmonary therapist.
 Physical activity 
 Try to do aerobic exercise daily. Aerobic exercise is any exercise that increases your heart rate, such as walking, swimming, or cycling. In cold weather, take the stairs in your home, go to the mall or shop.Exercise will help improve the condition of the body for the operation, as well as help facilitate and speed up the healing process.
 Stick to a healthy diet 
 Prior to surgery, try to have a well-balanced, healthy diet. If you need help with diet planning, ask your healthcare provider to refer you to a dietitian nutritionist.
 7 days before surgery 
 Follow your healthcare provider’s instructions when taking aspirin 
 If you are taking aspirin and any medicines containing aspirin, you may need to change your dose or not take them for 7 days before your surgery.Aspirin can cause bleeding.
 Follow your healthcare provider’s instructions.  Do not stop taking aspirin unless directed to do so.  For more information, read the resource Common Medicines Containing Aspirin and Other Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) or Vitamin E.
 Stop taking vitamin E, multivitamins, herbal remedies, and other dietary supplements 
 Stop taking vitamin E, multivitamins, herbal remedies, and other dietary supplements 7 days before surgery.These medicines can cause bleeding. For more information, read the resource Herbal Remedies and Cancer Treatments.
 2 days before surgery 
 Stop taking nonsteroidal anti-inflammatory drugs [NSAIDs]. 
 Stop taking NSAIDs such as ibuprofen (Advil ®  and Motrin ® ) and naproxen (Aleve ® ) 2 days before surgery. These medicines can cause bleeding.For more information, read the resource Common Medicines Containing Aspirin and Other Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) or Vitamin E.
 1 day before surgery 
 Record the time at which the operation is scheduled 
 An admissions officer will call you after 2:00 pm the day before your surgery. If your surgery is scheduled for a Monday, you will receive a call the previous Friday. If no one contacts you by 19:00, please call 212-639-5014.
 A staff member will tell you when you should come to the hospital for your surgery. You will also be reminded how to get to the ward.
 The operation will be performed at one of the following addresses:
 Josie Robertson Surgery Center 
 1133 York Avenue (at 61  st  Street) 
 New York, NY 10065
 Memorial Hospital 
 1275 York Avenue between 67  th  and 68  th  Streets 
 New York, NY 10065
 Instructions for eating before surgery 
  Do not eat after midnight before your surgery. This also applies to candy and chewing gum.
 Morning before surgery 
 Instructions for drinking beverages before surgery 
 You may drink a maximum of 12 ounces (350 ml) of water between midnight and 2 hours before your arrival time at the hospital. Don’t drink anything else.
  Do not drink any liquid two hours before your scheduled arrival time at the hospital.  This also applies to water.
 Take medication as directed 
 If your healthcare provider tells you to take some medicines in the morning before your surgery, take only those medicines with a small sip of water.Depending on the medications, this may be all or some of the medications you usually take in the morning, or you may not need to take them at all.
 Points to Remember 
 Wear comfortable, loose clothing.
 Do not use lotions, creams, deodorants, makeup, powder, perfume or cologne.
 Remove nail polish and decals.
 If you wear contact lenses, remove them and put on glasses. During surgery, contact lenses can injure your eyes.
 Do not wear metal objects. Remove all jewelry, including body piercings. The equipment used during the operation may cause burns if it comes into contact with metal.
 Leave your valuables at home.
 If your period (period) starts, use a sanitary towel, not a tampon. You will be given disposable underwear and a pad if needed.
 What to take with you 
 Your own breathing apparatus for the prevention of sleep apnea (eg CPAP apparatus), if available.
 Stimulating spirometer
 A Health Care Proxy Form, if you have completed it.
 Mobile phone and charger.
 A bag for storing personal items (such as glasses, hearing aids, dentures, dentures, wig, and religious items), if you have them.
 These are recommendations. Using these guidelines, your healthcare team will guide you on how to take care of yourself after your surgery.
 Upon arrival at the hospital 
 Various healthcare providers will ask you to name and spell your name and date of birth. This is for your safety. People with the same or similar names can be operated on on the same day.
 When it’s time to change before your surgery, you will be given a hospital gown, gown, and non-slip socks.
 Nurse appointment 
 You will meet with the nurse before your surgery.Tell her / him the doses of all medications you took after midnight and the times you took them (including all prescription and over-the-counter medications, patches, creams, and ointments).
 The nurse may place an intravenous (IV) line into one of the veins, usually in the arm or hand. If the nurse does not give you an IV, your anesthesiologist will do it when you are in the operating room.
 Meeting with anesthesiologist 
 You will also meet with your anesthesiologist before your surgery.This specialist:
 will review the medical record with you;
 asks if you have had any problems with anesthesia in the past, including nausea or pain;
 will talk about your comfort and safety during the operation;
 will tell you about the type of anesthesia you will receive;
 will answer your questions about anesthesia.
 Preparation for operation 
 Before surgery, you will need to remove your hearing aid, dentures, dentures, wig, and religious paraphernalia (if you have any of the above).
 You will go to the operating room yourself, or you will be taken there on a gurney. A member of the operating team will help you lie down on the operating table and put compression boots on your shins. They will inflate and deflate smoothly to improve blood flow in your legs.
 When you are comfortable on the table, the anesthesiologist will administer anesthesia through an IV line and you will fall asleep. Your IV line will also give you fluids during and after your surgery.
 During operation 
 When you fall asleep, a breathing tube will be inserted through your mouth into your windpipe to help you breathe.After the surgery is complete, surgical stitches will be placed on your incision. In addition, Steri-Strips  ™  (thin strips of surgical tape) or Dermabond ®  (surgical adhesive) may be applied to your incisions. The breathing tube is usually removed while you are still in the operating room.
 to come back to the beginning
 Post-operation 
 The information in this section will let you know what to expect after surgery, while you are in the hospital, and when you leave home.You will learn how to safely recover from surgery.
 As you read this section, write down the questions you want to ask your healthcare provider.
 Hospital 
 When you wake up from your surgery, you will be in the Post-Anesthesia Care Unit (PACU) or the postoperative care unit. The nurse will monitor your body temperature, heart rate, blood pressure, and oxygen levels.
 You may receive oxygen through a thin tube under your nose, or through a mask that covers your nose and mouth.You may also have a drain placed in your neck under the incision. If you have a drain, it will usually be removed the day after your surgery.
 The length of your hospital stay after surgery depends on your recovery. Most patients stay in the hospital for only 1 night. Nurses / nurses and other healthcare providers will teach you how to take care of yourself as you recover from surgery.
 Pain medications 
 You will experience pain after surgery.First, you will be given pain medication through an intravenous drip. As soon as you can swallow liquids, you will be given an oral pain medicine (medicine that you have to swallow).
 Your healthcare team will often ask you about your pain and give you medication as needed. If the pain persists, inform your healthcare team. Pain relief is essential to be able to use your incentive spirometer and get out of bed and walk.By controlling your pain, you can recover better.
 You may get a prescription for a mild pain reliever before you leave the hospital. You can take extra Strength Tylenol ®  instead. Talk with your healthcare provider about the possible side effects and when you need to switch to over-the-counter pain medications.
 Movement and walking 
 Moving and walking can help you reduce your risk of blood clots and pneumonia (lung infection).These activities will also help to resume gas and bowel movements (bowel movements). A nurse, physical therapist, or rehabilitation therapist can help you get around if needed.
 Read the material Call for help! Don’t fall! and find out what you can do to stay safe and avoid falls while in the hospital.
 Using an incentive spirometer 
 Use your incentive spirometer 10 times every hour when you are awake.This will help expand the lungs, which will prevent pneumonia from developing. For more information, see the resource How to use your incentive spirometer.
 Eating and drinking 
 A few hours after surgery, you will be able to absorb ice chips and drink fluids. It is normal to experience some discomfort when swallowing. You will gradually return to your normal diet. After the first night, you are not required to adhere to dietary restrictions.
 Ways to cope with hypocalcemia 
 Your health care provider will monitor your blood calcium levels after surgery and will prescribe a calcium supplement if needed. You may need to take it for several weeks until your parathyroid glands start working normally.
 If you feel numbness or tingling in your hands, feet, or around your mouth, tell your healthcare provider. These are signs of low blood calcium levels.
 Preparing for hospital discharge 
 Before you leave the hospital, your nurse will teach you how to care for your incision. The instructions will be recorded on the document you receive when you check out.
 Review your incisions with one of your healthcare providers before leaving the hospital. Remember what the cuts look like so you can notice their changes later.
 Most patients have only Steri-Strips on their incisions at discharge.Leave them in place until your first visit to your doctor after surgery. Your healthcare professional will examine them during your appointment. If your incisions are stitched, they will also be removed during your first visit to your doctor after surgery.
 Houses 
 Read the resource What You Can Do To Avoid Falls and find out what you can do to stay safe and avoid falls at home and during your visits to MSK.
 Completing the Recovery Tracker Postoperative Questionnaire 
 We need to know how you feel after you leave the hospital.To continue to provide you with medical care, we will submit questions to your MyMSK account daily for 10 days after you leave the hospital. These questions are called the Postoperative Recovery Tracker questionnaire.
 Complete the Recovery Tracker Postoperative Questionnaire every day no later than midnight (24:00). It only takes you 2-3 minutes. Your answers to these questions will help us understand how you feel and what you need.
 Based on your answers, we may ask you for more information or ask you to call the surgeon.You can always call your surgeon’s office if you have any questions. For more information, read the resource Recovery Tracker Postoperative Questionnaire.
 Pain relief 
 The time period over which people experience pain and discomfort can vary. Painful sensations may remain with you at the time of returning home. This does not mean that something is wrong with you.
 The following guidelines can help you relieve pain at home.
 Take your medicine as directed and as needed.
 If the prescribed medication does not relieve your pain, contact your healthcare provider.
 Do not drive or drink alcohol while you are taking prescription pain medication. Some prescription pain relievers can make you drowsy. Alcohol can worsen sedation.
 As the incision heals, the pain will decrease and you will need less pain medication.Over-the-counter pain relievers such as acetaminophen (Tylenol ® ) or ibuprofen (Advil ®  or Motrin ® ) can help relieve pain and discomfort.
 Follow your healthcare provider’s advice to stop taking your prescribed pain medication.
 Do not take any medications in excess of those indicated on the label, or follow the advice of a healthcare professional.
 Carefully read the labels on all medicines you take, especially if you have been prescribed a medicine that contains acetaminophen.Acetaminophen is found in many OTC and prescription drugs. Too much is bad for the liver. Do not take more than one acetaminophen product without talking to your healthcare team.
 Pain medications should help you get back on track. Take enough medication to keep you comfortable with your daily activities and exercise. A slight increase in pain with increasing physical activity is normal.
 Monitor the timing of your pain medication. They are most effective 30–45 minutes after ingestion. It is better to take the medicine at the first manifestations of pain, without waiting for its intensification.
 Certain prescription pain medications (such as opioids) can cause constipation (less frequent bowel movements than usual).
 Shower 
 You can shower 24 hours (1 day) after removing the surgical drain. If you have not had a drain installed, you can shower 48 hours after your surgery.
 Do not tilt your head back (as if you are looking at the ceiling) while showering for 4 weeks after surgery. You can direct water directly over the incision. Gently blot the incision dry with a clean towel or washcloth. Call your healthcare provider if you notice redness or discharge from your incision.
 Do not take a bath until you discuss it with your healthcare provider at your first visit after surgery.
 Cut Care 
 The location of the incision will depend on the type of surgery performed.If Steri-Strips are applied to your incision before discharge, they will come off and fall off on their own, or the surgeon will remove them during the first visit after surgery.
 A feeling of tightness along the incision may develop as it heals. This feeling can come and go. This can last from a week to several months or longer. This is normal and you shouldn’t worry about it. You may also feel numbness at and around the incision site. This is normal and will subside over time.
 Protect the incision area from sunlight for the first year after surgery. Your healthcare professional will tell you when you can safely use sunscreen. This usually occurs after the incision has completely healed.
 Taking a drug with thyroid hormones 
 If the thyroid gland is removed completely, you will need to take medication to replace the hormone that is produced by the thyroid gland. You will need to take it every day throughout your life.
 There are many thyroid hormone medications. One example is levothyroxine (Levoxyl ®  or Synthroid ® ). Read the resource Levothyroxine for more information.
 Your healthcare professional will prescribe your thyroid hormone medication and adjust the dosage. You may also need blood tests to make sure you are getting enough medication, but not too much. The healthcare professional will adjust the dose as needed.
 Taking calcium supplements 
 If after surgery you develop parathyroid dysfunction or hypocalcemia, you may need to take calcium supplements (eg Tums  ®  Ultra). You can buy it at your local pharmacy without a prescription. Your healthcare provider will determine the dosage.
 If you are taking calcium, your healthcare provider may give you a prescription for calcitriol (such as Calcijex ®  or Rocaltrol ® ).Calcitriol helps the body absorb calcium.
 Calcium can cause constipation, especially if you are taking pain medication. If you think this might be a problem for you, talk to your nurse. She / he will recommend a stool softener or laxative.
 Driving a car 
 Do not drive for 1 week after surgery. After this time, you will be able to drive a car if you turn your head and follow the traffic without any problems.
 Physical activity and exercise 
 Do not tilt your head back (as if you are looking at the ceiling) for at least 4 weeks after surgery. This stretches the incision. You can turn your head to the sides and tilt it down.
 Ask your healthcare provider how long it will take to lift heavy objects safely.
 Most patients should not lift anything heavier than 10 pounds (4.5 kg) for at least 2 weeks after surgery.
 Do not lift heavy objects, dumbbells, or upper body machines for at least 4 weeks after surgery. You can do exercises for your lower body.
 Aerobic exercise such as walking and climbing stairs can help you gain strength and improve your well-being. Gradually increase the walking distance. Climb the stairs slowly, resting and stopping as needed.
 Before proceeding to more intense exercise, consult your healthcare professional.
 Within a few weeks after the operation, you will notice that energy is gradually returning to you. Some people experience a period of fade and burst of energy for 1–2 months after surgery.
 Aftercare 
 Your first visit to the doctor will take place 7-10 days after your surgery. The nurse will give you directions on how to make an appointment, including the phone number to call. During the appointment, the surgeon will examine the incision. You will also discuss with him the results of your laboratory tests and the need for additional treatment.
 Many patients do not require additional treatment after surgery. However, if you have papillary thyroid cancer, you may need radioiodine therapy. The treatment team will discuss with you if this treatment is right for you. The treatment team consists of a surgeon, an endocrinologist (a doctor who treats glands and hormone-related diseases) and a medical radiologist. If radioiodine therapy is needed, the endocrinologist will tell you how the treatment will proceed.
 Blood tests 
 You will have thyroid function tests 6-8 weeks after your surgery. There will be two such studies: thyroid stimulating hormone (TSH) and free thyroxine (FT4). These studies will show if you have enough thyroid hormone in your bloodstream. Based on the results of these tests, your healthcare provider will adjust the dose of your thyroid medication you are taking.
 If you have your entire thyroid gland removed due to papillary cancer, you will need to have a thyroglobulin blood test 6 weeks after surgery.You will have this blood test every year so that the health care provider can keep track of the changes.
 For medullary thyroid cancer, 6 weeks after surgery, you will need to have blood tests called carcinoembryonic antigen (CEA) and calcitonin tests. You will have these blood tests every year so that the health care provider can keep track of the changes.
 to come back to the beginning
 When should you contact your healthcare provider? 
 Call your healthcare provider if you have any of the following symptoms:
 temperature 100.5 ° F (38 ° C) and above;
 discharge from the incision is observed;
 have trouble breathing;
 The skin around the incision is warmer than usual;
 increased discomfort around the incision;
 the skin around the incision begins to redden more than usual;
 There is or increased swelling around the incision;
 Numbness, twitching, or tingling sensations around the mouth, fingers, or toes;
 you have any questions or concerns.
 Contact information 
 Call your healthcare provider’s office Monday through Friday, 9:00 am to 5:00 pm.
 After 5:00 pm and on weekends and holidays, call 212-639-2000 and speak with the Medical Officer on duty.
 to come back to the beginning
 Support services 
 This section provides a list of support services that can help you prepare for and recover from surgery.
 As you read this section, write down the questions you want to ask your healthcare provider.
 MSK Support Services 
 For more information online, see the Cancer Types section of www.mskcc.org.
  Admitting Office  
 212-639-7606 
 Call if you have questions about hospitalization, including requesting a single room.
  Anesthesia Department  
 212-639-6840 
 Call if you have questions about anesthesia.
  Blood Donor Room  
 212-639-7643 
 Call for information if you would like to become a blood or platelet donor.
  Bobst International Center  
 888-675-7722 
 MSK accepts patients from all over the world. If you are from another country, call for help arranging your treatment.
  Counseling Center  
 646-888-0200 
 Psychological counseling helps many people.We provide counseling for individuals, couples, families and groups of individuals, and we provide medications to help you cope with anxiety or depression. To make an appointment, ask your healthcare provider for a referral or call the phone number above.
  Female Sexual Medicine and Women’s Health Program  
 646-888-5076 
 Cancer and cancer treatments can affect your sexual health.Our Women’s Sexual and Reproductive Medicine Program can help you if you have cancer-related sexual health problems such as premature menopause or fertility problems. Call for more information or to make an appointment. We can help you take action and address sexual health issues before, during and after treatment.
  Food Pantry Program  
 646-888-8055 
 The Food Pantry Program provides food to low-income patients during cancer treatment.For more information, contact your healthcare provider or call the phone number above.
  Integrative Medicine Service  
 646-888-0800 
 The Integrative Medicine Service offers a variety of services in addition to traditional health care. These services include music therapy, mind / body therapy, dance and movement therapy, yoga and tactile therapy.
  Male Sexual and Reproductive Medicine Program  
 646-888-6024 
 Cancer and cancer treatments can affect your sexual health. Our Sexual and Reproductive Medicine Program for Men can help you if you have cancer-related sexual health problems such as erectile dysfunction. Call for information or to make an appointment. We can help you take action and address sexual health issues before, during and after treatment.
  MSK Library  
 library.mskcc.org 
 212-639-7439 
 You can visit our library website or contact library staff for more information on a particular cancer. Alternatively, you can check out the LibGuides section on the MSK library website at libguides.mskcc.org
  Patient and Caregiver Education  
 www.mskcc.org/pe 
 Visit the Patient and Caregiver Education website to find educational materials in our virtual library.You can find learning resources, videos, and online programs.
  Patient and Caregiver Peer Support Program  
 212-639-5007 
 You may be encouraged to talk to someone who has received treatment like yours. Through our Patient and Caregiver Peer Support Program, you can talk to a former MSK patient or caregiver.Such conversations are confidential. You can communicate in person or by phone.
  Patient Billing  
 646-227-3378 
 Call if you have questions about preauthorization with your insurance company. This is also called preapproval.
  Patient Representative Office  
 212-639-7202 
 Call if you have questions about a health care power of attorney or concerns about caring for you.
  Perioperative Nurse Liaison  
 212-639-5935 
 Call if you have questions about who MSK will share your information with during surgery.
  Private Duty Nursing Office  
 212-639-6892 
 You can request the assistance of a Private Duty Nursing Office or Companions. Call for more information.
  Resources for Life After Cancer [RLAC] Program  
 646-888-8106 
 At MSK, patient care does not end after active treatment is completed. The Resources for Life After Cancer (RLAC) program is designed for patients who have completed their treatment and for their families. This program offers a variety of services such as workshops, workshops, support groups, and post-treatment counseling.She also helps with health insurance and employment issues.
  Social Work  
 212-639-7020 
 Social workers help patients, their families and friends cope with the challenges of cancer. They provide one-on-one counseling and support groups during your treatment and can help you connect with your children and other family members. Our social workers can also refer you to local agencies and programs, and provide information on additional financial resources if you are eligible.
  Spiritual Support  
 212-639-5982 
 Our chaplains (spirit guides) are ready to listen to and support family members, pray, connect with local clergy or religious groups, just comfort and lend a hand for spiritual help. Anyone can apply for spiritual support, regardless of their formal religious affiliation. The MSK Interfaith Chapel is located next to Memorial Hospital’s main lobby. It is open around the clock.If you have an emergency, call 212-639-2000. Ask to speak to the duty chaplain.
  Tobacco Treatment Program  
 212-610-0507 
 If you want to quit smoking, MSK has specialists who can help. Call for information.
  Virtual Programs  
 www.mskcc.org/vp 
 MSK Virtual Programs offer online training and support for patients and caregivers, even if you cannot come to MSK in person.Through interactive activities, you can learn more about your diagnosis and what to expect during treatment and how to prepare for the different stages of cancer treatment. Classes are held confidentially, free of charge and with the involvement of highly qualified medical professionals. If you would like to join the virtual training program, visit our website at www.mskcc.org/vp for more information.
 External support services 
  Organization Access-A-Ride  
 web.mta.info/nyct/paratran/guide.htm 
 877-337-2017 
 MTA New York offers ridesharing and escort services for people with disabilities who cannot use the bus or subway.
  Air Charity Network  
 www.aircharitynetwork.org 
 877-621-7177 
 Provides travel to treatment centers.
  American Cancer Society (ACS)  
 www.cancer.org 
 800-ACS-2345 (800-227-2345) 
 Offers a variety of information and services, including Hope Lodge, a free place to stay for patients and their caregivers during cancer treatment.
  Cancer and Careers website  
 www.cancerandcareers.org 
 A resource for educational materials, tools and information on various activities for working people with cancer.
  Cancer Organization  Care   
 www.cancercare.org 
 800-813-4673 
 275 Seventh Avenue (between West 25  th  Street and 26  th  Street) 
 New York, NY 10001 
 Provides consulting, support groups, educational workshops, publications, and financial assistance …
  Cancer Support Community  
 www.cancersupportcommunity.org 
 Provides support and educational materials for people facing cancer.
  Caregiver Action Network  
 www.caregiveraction.org 
 800-896-3650 
 Provides educational materials and support for people caring for loved ones with a chronic illness or disability.
  Corporate Angel Network  
 www.corpangelnetwork.org 
 866-328-1313 
 Offers free travel for medical treatment around the country through available seats on corporate flights.
  Gilda’s Club Organization  
 www.gildasclubnyc.org 
 212-647-9700 
 A place where men, women and children with cancer receive social and emotional support through communication, workshops, lectures and community events.
  Good Days Organization  
 www.mygooddays.org 
 877-968-7233 
 Offers financial assistance to cover copayments during treatment. Patients must have health insurance, they must meet a number of criteria, and they must be prescribed medications that are on the Good Days formulary.
  Healthwell Foundation  
 www.healthwellfoundation.org 
 800-675-8416 
 Provides financial assistance to cover copayments, health insurance premiums, and deductibles for certain drugs and treatments.
  Joe’s House  
 www.joeshouse.org 
 877-563-7468 
 Provides cancer patients and their families with a list of places to stay near treatment centers.
  LGBT Cancer Project Resource  
 http: // lgbtcancer.com / 
 Provides support and advocacy for the LGBT community, including online support groups and a database of LGBT tolerant clinical trials.
  LIVESTRONG Fertility Organization  
 www.livestrong.org/we-can-help/fertility-services 
 855-744-7777 
 Provides information on fertility and support for cancer patients whose treatment includes fertility risks and cured of cancer.
  Look Good Feel Better Program  
 www.lookgoodfeelbetter.org 
 800-395-LOOK (800-395-5665) 
 This program offers workshops to help you learn more positive perceive your appearance. For more information or to sign up for a workshop, call the above phone number or visit the program website.
  National Cancer Institute  
 www.cancer.gov 
 800-4-CANCER (800-422-6237)
  National Cancer Legal Services Network  
 www.nclsn.org 
 Free cancer advocacy program.
  National LGBT Cancer Network  
 www.cancer-network.org 
 Provides educational materials, training and advocacy for LGBT cancer survivors and at-risk patients.
  Needy Meds Resource  
 www.needymeds.org 
 Provides a list of programs that support patients in obtaining generic and registered brand drugs.
  NYRx Organization  
 www.nyrxplan.com 
 Provides prescription drug benefits to eligible current and former New York State public sector employees.
  Partnership for Prescription Assistance  
 www.pparx.org 
 888-477-2669 
 Helps eligible patients who do not have prescription drug coverage get free or low cost drugs.
  Patient Access Network Foundation  
 www.panfoundation.org 
 866-316-7263 
 Provides co-payment assistance for insured patients.
  Patient Advocate Foundation  
 www.patientadvocate.org 
 800-532-5274 
 Provides access to medical care, financial assistance, insurance assistance, job retention assistance, and access to a national directory of resources for people with poor health coverage.
  RxHope Organization  
 www.rxhope.com 
 877-267-0517 
 Provides assistance in getting drugs that people may not have enough money to buy.
 Thyroid Cancer Support Services 
  Support for People with Oral and Head and Neck Cancer (SPOHNC)  
 www.spohnc.org 
 800-377-0928 
 Provides information and support for patients with oral, head and neck cancers.
  Thyroid Cancer Survivors’ Association  
 www.thyca.org
  SHARE Organization  
 www.sharecancersupport.org 
 866-891-2392 
 Offers support groups for survivors of breast cancer, metastatic breast cancer and ovarian carcinoma in Manhattan, Queens, Brooklyn and Staten Island.
 to come back to the beginning
 Educational Resources 
 This section provides a list of the training materials that have been referenced in this manual. These materials will help you prepare for your surgery and recover safely from it.
 As you read this resource, write down the questions you want to ask your healthcare provider.
 to come back to the beginning
 Iodine deficiency diseases 
  IQ indices:  
  (intellectual coefficient) 
 25-50 – imbecilia 
 50-70 – moronism 
 70-90 – low intelligence 
  90-110 – norm  
> 110 – high intelligence
 In the 21st century, WHO has developed a new global concept for the elimination of iodine deficiency, the primary goal of which is to prevent brain damage associated with iodine deficiency and mental disorders in offspring to increase the intellectual potential of the world’s population.
 A program for the prevention of diseases caused by iodine deficiency has been developed in Russia. 
 Methodical instructions 2.3.7. 1064-01 
 “Control of the program of prevention of diseases caused by iodine deficiency by universal salt iodization” approved on July 27, 2001 and put into effect by the chief state physician of the Russian Federation on October 1, 2001 include: 
 • Use of iodized  table salt  as a method    iodine prophylaxis  
 • The use of iodine-containing  drugs with a fixed dose of iodine,  for  group and individual iodine prophylaxis:  
 medicinal value.
  The Union of Pediatricians in 2006 adopted recommendations on the use of dietary supplements in obstetrics and pediatrics. 
 The use of food additives and dietary supplements containing an unstandardized dose of iodine, including in combination with proteins and carbohydrates, cannot be recommended as group and individual prophylaxis for: 
 • pregnant women, 
 • lactating women, 
 • newborns, 
 • infants, 
 • children and adolescents
 Against the background of daily use of iodized salt up to 5 grams, iodine prophylaxis in obstetric practice should be mandatory, continuous, should be carried out with adequate doses and special drugs.
 To assess the adequacy of iodine intake for pregnant women, it is recommended to estimate the level of ioduria 
: the median ioduria during pregnancy should fluctuate between 150-250 μg / l. Median of iodine excretion in Nizh. region – 46 μg / L 
 (Tarasova N.I., 2010)
  Increased capture of radioactive isotopes of iodine during nuclear disasters 
 During the Chernobyl accident, 1986, radioactive iodine -131 accounted for 50-60% of the total radiation pollution. An increase in the incidence of thyroid cancer among children was noted 4 years after the accident.
 The most serious damage to the population in the first period of time is associated with isotopes of iodine. The half-life of Iodine-131 is 8.02 days and accounts for 50-60% of the total pollution. 
 How actively the thyroid gland captures iodine isotopes directly depends on the level of iodine supply in the region. 
 Iodine deficiency, experienced by the population of most affected regions, is the reason for the more intense uptake of iodine isotopes by the thyroid gland. 
 To protect the thyroid gland from radiation damage in iodine-deficient regions, it is necessary: ​​
 • to carry out continuous continuous mass, group and individual prevention of iodine deficiency with physiological doses of iodine in accordance with age norms; 
 • in the event of a nuclear disaster, an urgent appointment of pharmacological doses of iodine is required.
  Practical recommendations developed by the International Atomic Energy Agency and the International Commission on Radiation Protection (1991):  
 § The dose of potassium iodide prescribed in the event of a radiation hazard should be 130 mg, which is equivalent to 100 mg of iodine. Preference is given to tablets containing an individual dose of potassium iodide with a shelf life of at least 5 years. The tablets should be dissolved in water, milk or fruit juice. Iodine should not be taken on an empty stomach.
 § It is best to prescribe iodine before the onset of radiation contamination, during an accident or immediately after it. 
 § A single dose of iodine is usually sufficient. The question of re-administration of iodine should be decided taking into account the expected dose of thyroid exposure and the duration of the release of radioactive isotopes.
  Side effects of pharmacological doses of iodine:  
 • Intrathyroid: iodine-induced goiter, hypothyroidism and thyrotoxicosis.
 • Extrathyroid: gastrointestinal disorders, inflammation of the salivary glands (sialadenitis), allergic reactions and rash, headache.
  WHO recommendations on iodine prophylaxis after nuclear disasters 
 90,000 Additional use of iodine by women during pregnancy planning, during pregnancy and in the postpartum period
  What is the problem? 
 It is estimated that over 1.8 billion people worldwide are not getting enough iodine in their diets, posing a threat of iodine deficiency.Iodine is an indispensable component of the diet that the body needs in small amounts in order for the thyroid hormones to be produced. The World Health Organization (WHO) recommends adding iodine to salt to prevent problems caused by iodine deficiency. Women who are pregnant or breastfeeding require additional iodine intake, which puts them at greater risk of iodine deficiency. Breast milk contains iodine, which is essential for a baby.
  Why is this important? 
 The functional activity of the thyroid gland increases during pregnancy because the thyroid hormones produced by the mother (and the baby as pregnancy progresses) are necessary for the growth and development of the baby and for regulating the development of the brain and nervous system.Nerve tissue begins to develop as early as the second month of pregnancy. If iodine levels are too low in women during pregnancy or in infants during childhood, the damage may be irreversible. Studies have shown that severe iodine deficiency can interfere with the normal physical development of children and disrupt normal mental development, which leads to a decrease in intelligence. Less is known about the consequences of mild to moderate iodine deficiency. Too much iodine can also be harmful and have negative consequences for mothers and babies, such as overactive thyroid glands.
 Although salt is usually the main source of iodine, expert medical groups recommend that women in many countries take iodine supplements during and after pregnancy to meet their iodine requirements.
  What evidence have we found? 
 We searched for evidence in November 2016 and found 14 randomized controlled trials of iodine supplements in the form of tablets, capsules, drops, or injections before, during, or after pregnancy.Eleven trials involving over 2,700 women were included in the review. Eight trials compared iodine supplementation with no treatment or placebo, and three trials compared iodine supplementation in combination with other vitamins and minerals to vitamins and minerals without iodine added.
 Women who received iodine supplements were less likely to develop the adverse effects of hyperthyroidism (overactive thyroid gland) after childbirth (three trials involving 543 women), but were more likely to have nausea or vomiting during pregnancy (one trial involving 76 women). compared to those who did not receive iodine.One trial (365 women) found no difference in the number of women with increased thyroid activity during pregnancy. There was no clear difference in the number of women with an underactive thyroid gland (hypothyroidism), either during pregnancy (one trial involving 365 women) or postpartum (three trials involving 540 women) with supplemental iodine supplementation. There was no difference in the number of women who had an increase in thyroid antibodies during pregnancy (one trial, 359 women) and after childbirth (three trials, 397 women).We did not find clear differences between women who received iodine supplements and those who did not receive iodine supplements in terms of preterm birth (two trials, 376 women) or death in childbirth (two trials, 457 women), low birth weight weight (two trials, 377 infants), cases of underactive thyroid in neonates (two trials, 260 infants), or increased thyroid antibodies (one trial, 108 infants).
 The quality of the evidence was low or very low, mainly because only a small number of trials looked at each outcome, or because of limitations in study design.Most of the results came from one or two trials that included a small number of women. This means that we are not sure about the results.
  What does this mean? 
 The potential benefits and harms of any intervention must be weighed as part of the decision to use it. Our Cochrane Review provides a summary of the evidence, but there is insufficient data to draw any meaningful conclusions regarding the benefits and harms of routine supplemental iodine supplementation in women before, during, or after pregnancy.The limited information we found suggests benefits and risks associated with iodine supplementation. Additional research will help clarify the effects and safety of this intervention. Future trials should be conducted as randomized controlled trials, in a good practice and ethical manner, and include the outcomes listed in this review.