Is It Safe to Take 50,000 IU of Vitamin D?

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You’re at the doctor’s office when she hands you a prescription for a 50,000 international unit (IU) vitamin D capsule. But then you find out that most over-the-counter vitamin D supplements serve up a fraction of that amount, and that the recommended daily amount for adults under age 70 is 600 IUs. So is this mega-dose of vitamin D a good idea?

Yes, it’s generally safe to take 50,000 IUs once a week for a short periods of time—as long as you’re under the supervision of a healthcare provider, says Judith A. Smith, Pharm.D., a professor and director of the Women’s Health Integrative Medicine Research Program at UTHealth Houston McGovern Medical School in Texas. “Doctors prescribe this amount to correct low levels of vitamin D.”

Why Vitamin D Is So Important

Your body uses vitamin D to help you absorb calcium and phosphorus. These minerals are crucial for building bone and supporting healthy tissues, says Mary Bridgeman, Pharm. D., a clinical professor at Rutgers’ Ernest Mario School of Pharmacy in Piscataway, NJ. Falling short on vitamin D can set the stage for muscle and bone issues, such as osteoporosis.

Beyond bone health, vitamin D can impact your health in many other ways, too. “Receptors for vitamin D are found in cells throughout the body,” says Julie Stefanski, R.D.N., a spokesperson for the Academy of Nutrition and Dietetics based in York, PA. Research is still revealing how vitamin D affects your well-being, but it may be involved in the following health issues:

Cancer

Although the science is mixed when it comes to vitamin D and certain cancers, some promising research suggests that having higher levels of vitamin D may help protect against colorectal and breast cancers. One study found that people who took a 2,000 IU vitamin D supplement daily were about a third less likely to die of cancer compared to those who didn’t.

Colds and Other Respiratory Infections

Vitamin D is tied to your immune health, says Stefanski. “Vitamin D deficiencies can impact the production of immune system components that fight disease or halt cell growth.” One sign of a vitamin D deficiency is getting sick often, says Dr. Bridgeman.

Autoimmune Diseases

Taking a vitamin D supplement appears to reduce the chances of developing an autoimmune condition, such as rheumatoid arthritis or psoriasis, by 22%, according to a study published in the journal BMJ. Scientists based this finding on data from nearly 26,000 people who either took 2,000 IU of vitamin daily or a placebo pill.

Heart Health

Research shows that a vitamin D deficiency raises the risk of heart attack, stroke, and heart failure. But the role of D in heart disease still isn’t certain: Another analysis of more than 83,000 people found that people who took a vitamin D supplement for one year or more weren’t any more protected from heart attack or dying of heart disease.

Dementia

Having too-low blood levels of vitamin D upped the odds of developing dementia by 53%, reports a study in the journal Neurology. But experts agree that more study on the topic is needed.

Who Is at Risk for Vitamin D Deficiency?

Research shows that as many as 42% of adults are deficient in vitamin D, likely because people aren’t getting enough of the nutrient through their diet and sun exposure. Your body produces the vitamin when exposed UVB rays, but people are spending more time indoors and wearing sunscreen. (Skipping the sunscreen isn’t advised, though: “It’s crucial to wear sunscreen to protect against skin cancer,” says Dr. Bridgeman.)

It’s also tough to get the recommended daily amount of 600 IUs for adults ages 19 to 69 (800 IUs for those ages 70 and up) from foods, such as fortified cow’s and plant milks, fatty fish, and egg yolks. Certain conditions and traits also raise your risk:

• Chronic liver and kidney disease: These organs help turn vitamin D from the sun, food, and supplements into the active form that’s used by the body.

• Darker skin: Skin with more melanin, a pigment in the outer layer of skin, produces less vitamin D from the sun, says Kristin A. R. Gustashaw, MS, RD, an advanced level clinical dietitian at Rush University Medical Center in Chicago.

• Irritable bowel syndrome: This, along with celiac disease, gastric bypass, and other digestive tract issues, can interfere with vitamin D absorption.

• Obesity: Having excess fat may take vitamin D out of your bloodstream, leading to a deficiency.

Symptoms of vitamin D deficiency, such as fatigue, bone pain, and muscle weakness, are often ignored or mistaken for other conditions. It’s important that you ask your healthcare provider about your vitamin D status, especially if you have any of the conditions mentioned above.

Reasons to Take 50,000 IUs of Vitamin D

Your doctor may order a test to measure the amount of vitamin D in your blood. The optimal level is between 30 and 50 nanograms per milliliter (ng/mL). If the amount in your blood is below 20 ng/mL, your levels are inadequate; if it’s below 12 ng/mL, that means you’re deficient in the nutrient.

If that’s the case, your doctor may prescribe a megadose of 50,000 IUs to take once a week for six to 12 weeks to raise the level of vitamin D circulating in your body. “Vitamin D is a fat-soluble vitamin, which means that our body holds onto it,” says Dr. Bridgeman. The nutrient is stored in the liver and fatty tissues. And taking a huge dose each week means that you won’t have to remember to pop a pill daily. “The larger dose once a week is usually easier for people to remember,” says Dr. Bridgeman.

Safety Issues to Consider

When taken as prescribed, most people don’t have any side effects with this megadose of D, says Dr. Bridgeman. But it’s important that you take this high amount under your doctor’s supervision. Don’t try to take a high dose of vitamin D on your own.

The tolerable upper intake, or amount that’s likely to not cause harm in most people, is 4,000 IUs of vitamin D per day. Because the nutrient helps your gut absorb calcium, too much vitamin D can lead to a buildup of calcium in the blood. This condition is called hypercalcemia, and symptoms include:

• Fatigue

• Frequent urination

• Nausea and vomiting

If left untreated, hypercalcemia can lead to bone pain and kidney problems, such as kidney stones.

Overcoming a Vitamin D Deficiency

If your doctor prescribes you a 50,000 IU supplement, you’ll likely take it once a week for six to 12 weeks. After that, you’ll get another blood test to measure your level. If it’s still too low, you may need to continue taking the megadose for another six to 12 weeks.

If your vitamin D is back to normal, your doctor will likely recommend taking a daily over-the-counter supplement. Many experts feel that 400 to 800 IU is a good starting point for most adults, says Stefanski. But others recommend a higher amount of 1,000 to 2,000 IUs daily.

Whether you’re at risk for a deficiency or not, ask your healthcare provider about your vitamin D level. Because symptoms are often mild or vague, low vitamin D is often overlooked. If tests indicate a D deficiency, you can work with your doctor to come up with a plan, including potential supplements, to raise your level and safeguard your health.

Notes: This article was originally published June 5, 2014 and most recently updated February 13, 2023.

Cancer and Vitamin D: American Cancer Society. (2019.) “Are You Getting Enough Vitamin D?” https://www.cancer.org/latest-news/are-you-getting-enough-vitamin-d.html

Vitamin D and Colorectal Cancer: American Cancer Society. (2018.) “Vitamin D Levels Linked to Lower Colorectal Cancer Risk.” https://www.cancer.org/latest-news/vitamin-d-levels-linked-to-lower-colorectal-cancer-risk.html

Vitamin D and Breast Cancer: Cancer Research Prevention. (2021.) “Vitamin D as a Potential Preventive Agent For Young Women’s Breast Cancer.”
https://aacrjournals.org/cancerpreventionresearch/article/14/9/825/666827/Vitamin-D-as-a-Potential-Preventive-Agent-For

Cancer and Supplements: JAMA Network Open. (2020.) “Effect of Vitamin D3 Supplements on Development of Advanced Cancer.” https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2773074

Autoimmune Diseases: BMJ. (2022.) “Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial.” https://www.bmj.com/content/376/bmj-2021-066452

Heart Health: JAMA Cardiology. (2020.) “Vitamin D Supplementation and Cardiovascular Disease Risks in More Than 83,000 Individuals in 21 Randomized Clinical Trials.” https://jamanetwork.com/journals/jamacardiology/fullarticle/2735646

Dementia: Neurology. (2014.) “Vitamin D and the risk of dementia and Alzheimer disease.” https://n.neurology.org/content/83/10/920

Who’s At Risk for Vitamin D Deficiency: Nutrition Research. (2011.) “Prevalence and Correlates of Vitamin D Deficiency in US Adults.” https://pubmed.ncbi. nlm.nih.gov/21310306/

Optimal Vitamin D Levels: National Institutes of Health (2022.) “Vitamin D Fact Sheet for Health Professionals.” https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/

Obesity and Vitamin D: World Journal of Hepatology. (2014.) “Vitamin D deficiency in chronic liver disease.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4269909/

Vitamin D Deficiency: European Journal of Clinical Nutrition. (2020.) Vitamin D deficiency 2.0: an update on the current status worldwide
https://pubmed.ncbi.nlm.nih.gov/31959942/

Safety Issues to Consider: Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. (1998.) “A Model for the Development of Tolerable Upper Intake Levels.” https://www.ncbi.nlm.nih.gov/books/NBK114326/

Our Review Process

Safety of 50,000-100,000 Units of Vitamin D3/Week in Vitamin D-Deficient, Hypercholesterolemic Patients with Reversible Statin Intolerance

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Every second person has a deficiency of this vitamin, and its excess destroys the kidneys

• Health

More than half of Russians experience vitamin D deficiency. But as doctors say, this is not a reason to uncontrollably drink supplements with the “sunshine” vitamin. An overdose can seriously affect the kidneys and liver.

July 13, 2022

Source:

iStockphoto

According to experts, taking any vitamin should be taken as seriously as taking medication. They, too, can have side effects and consequences from an overdose. And vitamin D is no exception.

– Vitamin D overdose cannot be caused by prolonged exposure to the sun or by eating large amounts of foods rich in it. It develops against the background of taking supplements containing vitamin D in large quantities and is associated with its accumulation in the body,” explained Olga Malinovskaya, ^{head of the medical department of the federal network of medical laboratories KDL.}

According to the expert, an overdose of this vitamin in adults can lead to:

• accumulation of calcium in the blood (hypercalcemia),

• loss of appetite,

• nausea and vomiting, 007

• kidney problems.

That is why experts urge not to lean on supplements – the required dose should be determined individually and it is better if the doctor does this after studying the test results.

In children, the consequences can be even more serious, from calcium deposits in the internal organs to toxic hepatitis and insufficient kidney function. Experts recalled that when taking vitamin D supplements, it is necessary to periodically monitor the level of 25-OH vitamin D in total and the level of total calcium in the blood.

What is vitamin D responsible for

• for the absorption of phosphorus and calcium,

• regulates bone strength,

• ensures the normal functioning of the immune system and metabolism,

  9 0004

• reduces the risk of diabetes and cancer.

In Russia, to prevent vitamin D deficiency, people aged 18 to 50 years old, doctors recommend getting at least 600-800 IU of vitamin per day, over 50 – about 800-1000 IU.

Read HERE about vitamin D deficiency.

See also

Hospital bed instead of good

Taking a popular vitamin D supplement brought a British man to the hospital. After a visit to a private nutritionist, the man began taking a variety of over-the-counter supplements every day, including 50,000 international units (IU) of vitamin D three times a day—hundreds of times the recommended daily allowance.

The reaction of the body was not long in coming – soon the man began to suffer from nausea, abdominal pain, diarrhea and repeated bouts of vomiting, as well as leg cramps and ringing in the ears. After the onset of symptoms, he stopped taking the supplement, but his condition did not improve. Two months later, when the Briton was already admitted to the hospital, he lost more than 12 kilograms and began to suffer from kidney problems. Tests showed that he had hypervitaminosis D.

This case is reported by CNN, citing BMJ Case Reports. As the newspaper writes, unlike water-soluble vitamins, which the body can easily remove, vitamin D and its “relatives” – vitamins A, E and K are stored in the liver and fat cells until they are needed. Because of this, consuming much more than the recommended daily dose can lead to toxicity.

See also

Where to get vitamin D

The body produces enough vitamin D when exposed to sunlight. In fact, spending 10 to 15 minutes at the beach in a swimsuit in the summer provides between 10,000 and 20,000 IU of vitamin D3 in fair-skinned adults, according to CNN experts. It should be borne in mind that being under the scorching sun for a long time is not recommended due to the risk of skin cancer, and sunscreens can reduce the body’s ability to process this vitamin.

You can also get vitamin D from food. In addition to enriched foods, it is contained in

Text author: Anastasia Romanova

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Vitamin D: how to take, norms for children and adults

1. What is vitamin D
2. Benefit
3. Vitamins D2 and D3: what is the difference
4. Shortage
5. Oversupply
6. Sun and Vitamin D
7. How to get vitamin D from food
8. Preservation of vitamin D in foods
9. How to replace the sun
10. Physician’s comment

What is vitamin D and why is it needed?

The main function of vitamin D is to promote the absorption of calcium and phosphorus. This substance strengthens bones and helps brain function, which is especially important for children during their growth period. Vitamin deficiency leads to a breakdown and weakening of the immune system, a predisposition to colds, diseases of the teeth and bones [1].

How much vitamin D you need depends on many factors. These include age, race, seasonality, sun exposure, clothing, and more. The US Institute of Medicine recommends that an average daily dose of 400–800 IU, or 10–20 micrograms, is sufficient for 97.5% of people [2]. However, some studies have shown that the daily dose should be higher if you rarely go outside. So, for healthy people there are recommendations in the range of 1120-1680 IU. At the same time, patients with deficiency are prescribed up to 5000 IU [3]. People who are overweight or obese may also need more vitamin D [4]. In any case, do not take any vitamins without a doctor’s prescription.

Tsaturyan Sofya Sergeevna, endocrinologist, pediatric endocrinologist of the network of clinics Family:

“According to the results of an age-specific analysis, a stepwise scheme for prescribing vitamin D was proposed: for children under the age of 4 months, a daily intake of 500 IU / day is recommended (for premature babies – 800-1000 IU / day), from 4 months to 4 years – 1000 IU / day, 4-10 years old – 1500 IU / day, 10-16 years old – 2000 IU / day of vitamin during the year.

Pregnancy dose of vitamin D up to 4000 IU

Proven benefits of vitamin D

Fights disease

Studies confirm that vitamin D reduces the risk of multiple sclerosis and cardiovascular disease [5] [6]. A sufficient amount of the substance in the body is associated with a lower likelihood of colds and flu [7].

Reduces symptoms of depression

Vitamin D affects mood [8]. Surveys confirm that patients diagnosed with depression felt better after a course prescribed by doctors. Another study involved people with fibromyalgia. Scientists have indicated that vitamin D deficiency is more common in those who experience increased anxiety and depression [9].

© Michele Blackwell/Unsplash

Supports weight management

People who took daily calcium and vitamin D supplements were able to shed excess weight faster than patients who received placebo [10]. Doctors have proven that extra calcium and vitamin D suppress excessive appetite.

Improves stamina

Studies of 310 adults, 67% women, spanned four weeks to six months. Scientists have concluded that vitamin D can increase the physical strength of the upper and lower extremities [11].

Vitamins D2 and D3: the difference

There are two forms of vitamin D in the diet:

1. Vitamin D2 (ergocalciferol): found in some mushrooms.
2. Vitamin D3 (cholecalciferol): found in fatty fish, fish oil and egg yolks. It is mainly produced by ultraviolet radiation.

D3 is the more potent of the two types and increases blood levels of vitamin D almost twice as much as D2 [13]. Any excess of the substance is stored in the body for later use. Every cell has a receptor for D vitamins, as they are essential for many processes, including bone health and immune system function [14].

What Causes Vitamin D Deficiency

Vitamin D acts as a hormone, produced from cholesterol when exposed to sunlight. Although it is found in some foods, it is quite difficult to make up for the deficiency through nutrition alone. The recommended daily dose for an adult is 400-800 IU, but sometimes doctors advise to consume more. In Russian recommendations 2000 IU. According to a 2011 study, 41.6% of US adults are vitamin D deficient. This number reaches 69.2% among Hispanics and 82.1% among African Americans [15]. Scientists identify several risk factors that affect the lack of a substance in the body:

• dark skin;
• overweight;
• lack of fish and dairy products in the diet;
• distance from the equator, living in regions where there is little sun.
• overabundance of funds with SPF protection;
• inactive lifestyle, long stay indoors.

The most obvious factor in the lack of this vitamin is the lack of sun, prolonged exposure to indoors, especially without windows [16]. As people age, their skin’s response to UV light decreases, and a sedentary lifestyle exacerbates the problem. Closed clothing also prevents the production of the substance, even if you walk all day. Moreover, the darker the skin, the higher its protection from the sun, respectively, previtamin is supplied in smaller quantities. Keep in mind that it lingers in adipose tissue, so being overweight is also the cause of poor absorption of the vitamin.

Only a doctor can diagnose vitamin deficiency. Therefore, it is important to seek the advice of a specialist, and not to make independent appointments.

Too much vitamin D

Most people don’t get enough vitamin D, so supplements are common. However, this substance can accumulate and reach toxic levels in the body, especially as a result of uncontrolled use of pharmaceutical drugs. Vitamin D intoxication occurs when its blood level rises above 150 ng/mL (375 nmol/L). Because the vitamin accumulates in adipose tissue and slowly enters the bloodstream, the effects of toxicity may persist for several months after supplementation is stopped [17]. The main effects of an excess of vitamin D:

1. Blood parameters. Doctors rely on figures of 40–80 ng/mL (100–200 nmol/L). Their increase to values ​​of 100 ng. / ml (250 nmol / l) signal danger [18]. In one study, researchers looked at data from 20,000 people over a ten-year period. Only 37 people were found to have levels above 100 ng/mL (250 nmol/L) and only one person had true toxicity at 364 ng/mL (899 nmol/L) [19].
2. Elevated calcium levels. Vitamin D helps to better absorb calcium from food, this is one of its main roles in the body. However, hypercalcemia leads to dangerous symptoms such as indigestion, increased fatigue, abdominal pain, dizziness, and confusion. Normal blood calcium levels are 8.5–10.2 mg/dL (2.1–2.5 mmol/L). One study included 10 people who developed excessive calcium levels after taking high doses of vitamin D to correct a deficiency [20]. Four of them experienced nausea and vomiting, and three of them lost their appetite.
3. Stomach problems. Discomfort and diseases associated with digestion, including irritable bowel syndrome, may also indicate elevated calcium levels associated with vitamin D intoxication [21]. In one reported medical case, such symptoms developed in a 1.5-year-old child who was given 50,000 IU of vitamin D3 for three months [22]. They disappeared some time after the supplements were eliminated.
4. Loss of bone mass. Because vitamin D plays an important role in calcium absorption and bone metabolism, getting it is critical to maintaining bone strength. However, an excess of the substance leads to the opposite effect. Although many of the symptoms of vitamin D overuse are associated with high blood calcium levels, some researchers suggest that the consequence of increased dosage is low vitamin K2 levels [23]. One of the most important functions of the latter is to retain calcium in the bones and remove it from the blood. An excess of vitamin D reduces the activity of vitamin K2 [24].
5. Renal failure. Too much vitamin D leads to kidney damage. In one case study, a patient was hospitalized due to kidney failure, elevated blood calcium levels, and other symptoms after receiving vitamin D injections prescribed by a physician [25]. In another medical experiment involving 62 people who received injections of excessively high doses of vitamin D, kidney failure was found in every patient. Moreover, regardless of whether they had healthy kidneys or previously diagnosed diseases associated with them [26].

However, it is not possible to achieve dangerous levels of the vitamin in the blood due to prolonged exposure to the sun or food alone.

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How the sun helps produce vitamin D

The body converts UV rays into chemicals that become vitamin D3. Cholesterol processes previtamin D – it passes through the blood through the liver and kidneys, after which it turns into calcitriol. To replenish the amount of vitamin needed by the body, you need to be in direct sunlight, while more than half of the skin should be open. Studies show that the brighter the sun, the less time it takes to get vitamin D. Also, experts have calculated that in England it is enough to be outside for 13 minutes three times a week at noon. Try to follow the rules of tanning and protect the skin from burns.

Most residents of the northern regions should not expect to get their vitamin D from the sun alone. Even when you are on vacation in hot countries, and most of the time you are in the city, it is unlikely to be enough. Therefore, it is important that the vitamin enters the body, including with food. If you are diagnosed with a vitamin deficiency, your doctor will likely recommend adding meals to your diet daily with ingredients that are high in vitamin D. For severe deficiency, high-dose tablets or drops are prescribed.

How to get vitamin D from food

The Recommended Daily Allowance (DV) is 800 IU (20 µg) of vitamin D per day from food [27]. Food of animal origin is suitable for replenishing stocks: cheese, fish oil, kefir, egg yolk, butter, fish and oysters. Cod liver oil is the record holder for the content of vitamin D: in a teaspoon it is about 448 IU. Some plant foods also contain it, such as parsley, mushrooms, nettles, soy milk, and orange juice. Sometimes manufacturers additionally fortify foods with vitamin D by adding it to yogurt, milk, or oatmeal. It should be borne in mind that the content of the substance decreases during heat treatment. Before transportation, the fish is frozen, and before use it is cooked under the influence of high temperatures, as a result, some of the useful properties disappear.

How to preserve vitamin D in foods

In order to retain the maximum amount of useful substances in dishes, it is better not to soak meat and fish in water before cooking. Try defrosting them slowly, leaving them at room temperature. It is most useful to cook dishes by steaming, frying on the grill or baking in foil. Do not reheat food prepared the day before – this significantly reduces its beneficial properties. In addition, some products are dangerous to re-heat exposure.

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Sun substitutes

Doctors advise adults to get at least 600 IU (international units) of vitamin D. These figures are higher for pregnant and breastfeeding women. The only sure way to replenish vitamin reserves without ultraviolet radiation is to use pharmaceutical preparations. As a rule, they are prescribed to children in the cold season. The “sunshine vitamin” is difficult to obtain in the right amount only through food (for example, you have to eat 20 eggs daily). It is much easier to use a water-soluble preparation or fish oil capsules (especially cod liver oil). Vitamin D overdose is unlikely unless you are taking more than 10,000 IU per day for a long time. However, before buying pharmacy drugs, you need to consult a therapist and take a blood test.

Expert comment

Tsaturyan Sofya Sergeevna, endocrinologist, pediatric endocrinologist of the Semeynaya clinic network

Vitamin D is taken strictly after meals. The vitamin is fat-soluble, and so it is better absorbed. Clinical guidelines use both an oil form and an aqueous solution. In our country, only liquid forms of vitamin D are allowed.