What are the potential health consequences of taking too many vitamins. How can you recognize the subtle signs of vitamin overdose. Which three nutrients require special attention when it comes to overconsumption.

The Hidden Dangers of Vitamin and Mineral Overconsumption

In today’s health-conscious world, the abundance of fortified foods and dietary supplements has made it increasingly easy to exceed recommended daily intakes of vitamins and minerals. While proper nutrition is crucial for overall health, consuming excessive amounts of certain nutrients can lead to unexpected and potentially harmful side effects.

Johanna Dwyer, RD, a senior research scientist with the National Institutes of Health’s Office of Dietary Supplements, emphasizes that obtaining nutrients from unfortified foods is generally safe. The real concern lies in the combination of supplements, fortified foods, and fortified beverages.

Common Misconceptions About Vitamin Intake

Many individuals mistakenly believe that consuming more vitamins and minerals than recommended will provide additional health benefits. However, this is not the case. In fact, exceeding the recommended daily intake can potentially lead to adverse effects on one’s health.

• Excessive vitamin C or zinc intake may cause nausea, diarrhea, and stomach cramps
• Too much selenium could result in hair loss, gastrointestinal upset, fatigue, and mild nerve damage
• Overconsumption of vitamin A or D can lead to more severe health complications

Identifying the Signs of Vitamin Overconsumption

While severe vitamin toxicity is relatively rare, subtle signs of overconsumption may be more common than we realize. Dr. David Katz, director of the Yale University Prevention Research Center, notes that these symptoms can be easily overlooked or attributed to other causes.

Subtle Indicators of Excessive Vitamin Intake

Recognizing the early signs of vitamin overconsumption is crucial for maintaining optimal health. Some subtle symptoms to be aware of include:

• Difficulty sleeping or concentrating
• Nerve problems, such as numbness or tingling
• Increased irritability
• Mild gastrointestinal discomfort

It’s important to note that these symptoms may vary depending on the specific nutrient being consumed in excess.

The Impact of Food Fortification on Nutrient Intake

The trend of fortifying foods with additional vitamins and minerals has created a new challenge for consumers and healthcare professionals alike. Dr. Katz expresses concern about the practice of “garnishing the food supply with overfortification,” highlighting the difficulty in tracking total nutrient intake throughout the day.

The Shift in Food Manufacturing Focus

Food manufacturers have shifted their focus from removing potentially harmful ingredients to adding trendy nutrients. This practice has made it increasingly challenging for consumers to accurately gauge their daily nutrient intake.

As a result, healthcare providers must be aware of the potential for introducing new dietary imbalances due to this widespread fortification practice.

Three Nutrients to Watch: Vitamin D, Calcium, and Folic Acid

While all vitamins and minerals can potentially cause issues when consumed in excess, Johanna Dwyer identifies three nutrients that require special attention: vitamin D, calcium, and folic acid.

Vitamin D: The Double-Edged Sword

Vitamin D has gained significant attention for its numerous health benefits, but excessive intake can lead to serious complications. Adults who regularly exceed the safe upper limit of 4,000 international units (IUs) daily may be at risk of developing heart problems.

Calcium: Balancing Bone Health and Heart Health

While calcium is essential for strong bones and teeth, overconsumption can have negative effects on cardiovascular health. It’s crucial to find the right balance and avoid excessive supplementation without proper guidance from a healthcare professional.

Folic Acid: A Success Story with Potential Drawbacks

The fortification of grain products with folic acid has been a public health success, reducing birth defects by 25% to 50%. However, this practice has also raised concerns about potential overconsumption.

Regularly exceeding the safe upper limit of 1,000 micrograms of folic acid per day from fortified foods and supplements may mask the signs of vitamin B12 deficiency in older adults. This is particularly concerning as untreated vitamin B12 deficiency can lead to permanent nerve damage.

The Importance of Proper Dosing and Professional Guidance

To avoid the potential risks associated with vitamin and mineral overconsumption, it’s crucial to adhere to recommended dosages and seek professional guidance when considering supplements.

Guidelines for Safe Supplement Use

Andrew Shao, PhD, senior vice president of scientific and regulatory affairs for the Council for Responsible Nutrition, offers reassurance regarding basic multivitamins. He states that most multivitamins have a wide margin of safety, even when combined with fortified foods.

However, it’s essential to follow these guidelines for safe supplement use:

1. Stick to supplements that provide no more than the daily value of vitamins and minerals
2. Consult with your doctor about any supplements you’re taking, including the specific doses
3. Be aware of your total nutrient intake from both supplements and fortified foods
4. Pay attention to any unusual symptoms that may indicate overconsumption

The Role of Natural Food Sources in Meeting Nutritional Needs

While supplements and fortified foods can play a role in meeting nutritional needs, it’s important not to overlook the value of naturally nutrient-rich foods.

The Safety of Natural Folate Sources

Johanna Dwyer emphasizes that there’s no need to worry about foods naturally rich in folate. In fact, she suggests that most people can now get enough folic acid without relying on supplements, thanks to the fortification of grain products.

Balancing Supplementation with Whole Food Nutrition

A balanced approach to nutrition involves prioritizing whole, unprocessed foods while using supplements judiciously to fill specific nutritional gaps. This strategy helps minimize the risk of overconsumption while ensuring adequate nutrient intake.

The Future of Nutrient Fortification and Supplementation

As our understanding of nutrition continues to evolve, so too must our approach to food fortification and supplementation. The challenge lies in striking a balance between addressing nutritional deficiencies and preventing overconsumption.

Potential Solutions to Overfortification

To address the concerns raised by overfortification, several potential solutions could be explored:

• Implementing more precise fortification strategies based on population needs
• Improving labeling and consumer education about nutrient content in fortified foods
• Developing personalized nutrition recommendations based on individual needs and health status
• Encouraging regular nutritional assessments to identify potential imbalances or excesses

Empowering Consumers to Make Informed Decisions

As the landscape of nutrition continues to evolve, it’s crucial to empower consumers with the knowledge and tools necessary to make informed decisions about their vitamin and mineral intake.

The Importance of Nutritional Literacy

Improving nutritional literacy among the general public is essential for promoting healthy supplement use and preventing overconsumption. This includes understanding the role of different nutrients, recognizing reliable sources of information, and interpreting nutrition labels accurately.

Collaborative Approach to Nutritional Health

Achieving optimal nutritional health requires a collaborative effort between consumers, healthcare providers, food manufacturers, and regulatory bodies. By working together, we can create a more balanced and personalized approach to nutrition that minimizes the risks of vitamin and mineral overconsumption while ensuring adequate intake for all individuals.

In conclusion, while vitamins and minerals are essential for our health, it’s crucial to approach supplementation and fortified foods with caution and awareness. By staying informed, seeking professional guidance, and prioritizing a balanced diet rich in natural, whole foods, we can harness the benefits of proper nutrition while avoiding the potential pitfalls of overconsumption.

Taking Too Many Vitamins? Side Effects of Vitamin Overdosing

The health consequences of going overboard.

Written by Cari Nierenberg

• Supplements: Check the Dose
• Subtle Signs You’re Getting Too Much
• Three Nutrients to Watch

Nowadays, everything from bottled water to orange juice seems to have souped-up levels of vitamins and minerals in it. That may sound like a way to help cover your nutritional bases, especially if your diet is less than stellar. But routinely getting an overload of vitamins and minerals can hurt you.

Too much vitamin C or zinc could cause nausea, diarrhea, and stomach cramps. Too much selenium could lead to hair loss, gastrointestinal upset, fatigue, and mild nerve damage.

While most people aren’t getting megadoses, if you eat a fortified cereal at breakfast, grab an energy bar between meals, have enriched pasta for dinner, and take a daily supplement, you could easily be over the recommended daily intake of a host of nutrients.

Here’s what you need to know to avoid overdoing it.

Chances are, the unfortified foods you eat aren’t a problem. “It’s pretty hard to overdo it from food alone,” says Johanna Dwyer, RD, a senior research scientist with the National Institutes of Health’s Office of Dietary Supplements.

So you’ll want to think about the supplements you take and fortified foods or drinks.

“Most people don’t realize there’s no real advantage to taking more than the recommended amounts of vitamins and minerals, and they don’t recognize there may be disadvantages,” Dwyer says.

“If you’re taking a supplement, stick to one that’s no more than the daily value,” Dwyer says. (Daily value is the amount of a vitamin or nutrient that a person should get for optimum health.)

Talk with your doctor about any supplements you’re taking, including vitamins and minerals, and the dose you’re taking, too. That way, your doctor can help you keep doses in a safe range.

“If you’re taking a basic multivitamin, there’s no need to fear taking too much,” says Andrew Shao, PhD, senior vice president of scientific and regulatory affairs for the Council for Responsible Nutrition, a trade group for the supplements industry.

“Most multivitamins have such a wide margin of safety that even when you’re combining them with fortified foods, it’s still not going to cause you to keel over,” Shao says.

“I have not seen someone off the street who was taking a toxic level of vitamin A or D — those are very unusual,” says David Katz, MD, director of the Yale University Prevention Research Center in New Haven, CT, whose medical practice specializes in nutrition. “What I’m more likely to see is a person with a dosing level of supplements that’s higher than optimal.”

Scientists don’t yet know if routinely getting a little bit too much of a vitamin or mineral (as opposed to a megadose) is a problem, Katz says.

“There might be hints of concern, but they would be very subtle signs,” he says.

These fairly mild symptoms may include difficulty sleeping or concentrating, nerve problems such as numbness or tingling, or feeling more irritable — depending on the nutrient that’s going overboard.

The bigger concern, Katz says, is that we’re “garnishing the food supply with overfortification. “

He says manufacturers have shifted their focus from what they’ve taken out of food — such as its fat, sugar, or salt — to what they’re putting in, whether it’s vitamin D, probiotics, or omega-3 fats — whatever nutrient is in vogue.

“When more and more foods are enhanced, it becomes impossible for consumers to know what dose they’re getting over the course of a day,” Katz says. “Clinicians have to realize we might be introducing new dietary imbalances because of this practice.”

Dwyer says vitamin D, calcium, and folic acid are three nutrients you may get too much of, especially through supplements.

Adults who regularly far exceed the 4,000 international units (IUs) daily safe upper limit for vitamin D might may end up with serious heart problems.

Folic acid is added to enriched grain products — white flours, pasta, rice, breads, and cereals — to help prevent birth defects in babies due to folic acid deficiency in pregnant women. While folic acid fortification has cut the number of birth defects by 25% to 50%, it might have created other health concerns in people getting too much.

It’s not hard to get more than 1,000 micrograms of folic acid a day (the safe upper limit for adults) from fortified foods and supplements on a regular basis. Doing so might hide the signs of a vitamin B12 deficiency in older adults. Vitamin B12 deficiency can sometimes lead to permanent nerve damage if left untreated.

There’s no need to worry about foods that are naturally rich in folate.

“Most people can now get enough folic acid without having to rely on supplements,” Dwyer says.

In fact, she says, “most people have no problem [with getting too much vitamins or minerals] if they start with food, which is the healthiest and safest way to get them.”

Top Picks

7 Popular Supplements With Potential Hidden Risks

When it comes to supplements, there’s so much hype about their potential benefits that it can be hard to separate fact from fiction. While it’s true that vitamins and minerals are essential to health, it’s not true that taking them in pill, capsule, or powder form — especially in megadoses — is necessary or without risks.

For one thing, dietary supplements can sometimes interact with each other, as well as with over-the-counter (OTC) and prescription medication. In addition, unlike with drugs, the U.S. Food and Drug Administration (FDA) is not authorized to review dietary supplements for safety and effectiveness before they are marketed. It’s up to manufacturers to ensure that their products do not contain contaminants or impurities, are properly labeled, and contain what they claim. In other words, the regulation of dietary supplements is much less strict than it is for prescription or OTC drugs.

In March 2023, the FDA unveiled its new Dietary Supplement Ingredient Directory, a web page intended to help the public stay informed about the ingredients used in dietary supplements. Consumers can use the directory to look up ingredients used in products marketed as dietary supplements and find out what the FDA has said about that ingredient and whether the agency has taken any action pertaining to the ingredient.

According to the FDA, more than half of Americans take herbal or dietary supplements daily, with a report by Grandview Research noting the dietary supplements market was valued at $151.9 billion worldwide in 2021.

Used properly, some supplements may improve your health, but others can be ineffective or even harmful. For example, a systematic review published in the August 2019 Annals of Internal Medicine analyzed the potential effects of nutritional supplements on cardiovascular health, mainly heart attack and stroke, and found that few supplements help prevent heart disease — only omega-3 fatty acids and folic acid were effective. The same went for dietary changes, except for a low-salt diet.

Other research published the same year, involving self-reported dietary habits from a group of Americans, linked daily doses of more than 1,000 milligrams (mg) of calcium to a higher risk of death from cancer (though the National Cancer Institute notes that other studies suggest the opposite). Furthermore, the data showed that people who took in adequate amounts of magnesium, zinc, and vitamins A and K had a lower risk of death — but only if they got those nutrients from food rather than supplements.

“Buyer beware,” warns JoAnn Manson, DrPH, MPH, MD, the chief of the division of preventive medicine at Brigham and Women’s Hospital in Boston and a professor of epidemiology at the Harvard T.H. Chan School of Public Health in Cambridge, Massachusetts. “Many supplements on the market have not been rigorously tested. Very few supplements have been shown to be of benefit.” And, she says, many carry unsubstantiated health claims.

Confused? National Institutes of Health (NIH) fact sheets provide detailed information on the benefits and risks of individual vitamins and minerals, as well as herbal supplements. And if you’re managing an underlying health condition (especially if you’re taking medication) or are pregnant or breastfeeding, play it safe and have a conversation with your healthcare team before adding any new supplement to your regimen.

While supplement trends come and go, here are seven supplements that historically have been popular — and in all cases, experts recommend taking them carefully, if at all.

1. Vitamin D: Too Much Can Harm Your Kidneys

Vitamin D promotes calcium absorption in the body, and having enough is central to health and well-being, offering the promise of protecting bones and preventing bone diseases like osteoporosis, per the NIH. Supplemental vitamin D is popular because it’s difficult (if not impossible for some) to get enough from food.

Also, as the Centers for Disease Control and Prevention (CDC) notes, our bodies make vitamin D when bare skin is exposed to direct sunlight, but increased time spent indoors and widespread use of sunblock, as a necessary way to prevent skin aging and skin cancer, has minimized the amount of vitamin D many of us get from sun exposure.

But vitamin D supplements are a tricky topic. Sometimes, it can seem that guidelines and research contradict each other. The truth is, enthusiasm for vitamin D supplements is outpacing the evidence.

For example, when healthy pre- and post-menopausal women take vitamin D (up to 400 international units, or IU), it does not necessarily prevent them from breaking bones, according to a 2018 U.S. Preventive Services Task Force recommendation.

And high doses are not a good option. In healthy people, vitamin D blood levels higher than 100 nanograms per milliliter can trigger extra calcium absorption — and lead to muscle pain, mood disorders, abdominal pain, and kidney stones, notes the Cleveland Clinic. It may also raise the risk of heart attack and stroke.

“More is not necessarily better when it comes to micronutrient supplements,” says Dr. Manson.

That said, vitamin D supplements may benefit certain people, including those at risk of deficiency, such as individuals with darker skin, certain health conditions, and older adults, per MedlinePlus. The most recent American Geriatrics Society consensus statement specifically suggests that people older than 65 can help reduce the risk of fractures and falls by supplementing their diet with at least 1,000 IU of vitamin D per day, in addition to taking calcium supplements and eating vitamin D–rich foods.

Anyone can bolster their vitamin D levels by spending brief periods in the sun without sunblock — about 10 to 15 minutes a day, according to the NIH.

Keep in mind that vitamin D supplements and medications can interact with each other. Meds that don’t mix well with vitamin D include the weight loss drug orlistat (Xenical, Alli), various statins, such as atorvastatin (Lipitor), thiazide diuretics (such as Hygroton, Lozol, and Microzide), and corticosteroids like prednisone (Deltasone, Rayos, Sterapred), according to the NIH.

2. St. John’s Wort: Avoid Drug Interactions

St. John’s wort is a plant used as a tea or in capsules, with purported benefits for depression, attention-deficit hyperactivity disorder, menopause symptoms, insomnia, kidney and lung issues, obsessive-compulsive disorder, wound healing, and more, notes the NIH.

Small studies have shown St. John’s wort to be effective at treating mild depression. For example, a review of short-term studies looked at 27 clinical trials with about 3,800 patients and suggested that the herbal remedy worked as well as certain antidepressants at decreasing symptoms of mild to moderate depression.

But, says Denise Millstine, MD, an internist in the department of integrative medicine at Mayo Clinic in Phoenix, Arizona, “the biggest issue with St. John’s wort is its medication interactions.”

A study found that in 28 percent of cases when St. John’s wort was prescribed between 1993 and 2010, it was administered in dangerous combinations with antidepressant or anti-anxiety medication, statins, the blood-thinning drug warfarin (Coumadin), or oral contraceptives. For example, combining St. John’s wort with an antidepressant can cause serious complications, including a life-threatening increase in the brain chemical serotonin, according to the National Center for Complementary and Integrative Health.

St. John’s wort may also reduce the effectiveness of other medications, including birth control pills, chemotherapy, HIV or AIDS medication, and medicine to prevent organ rejection after a transplant, according to the NIH. Before you take St. John’s wort, read up on potential drug interactions and ask your doctor about the risks and benefits of this supplement, as well as how it compares to your other options.

3. Calcium: The Excess May Settle in Your Arteries

Calcium is essential for a strong skeleton, but as with all nutrients, too much of this mineral may be harmful. As the NIH notes, more than 2,500 mg per day for adults ages 19 to 50, and more than 2,000 mg per day for individuals 51 and over, can lead to problems.

With calcium supplements, hardened arteries, or atherosclerosis, and a higher risk of heart disease, are risks, though research is mixed, according to the Cleveland Clinic.

“Get calcium from your diet if you can,” advises Dr. Millstine, noting that research shows that calcium is better absorbed through food than through supplements. In a study, researchers analyzed a group of about 5,450 healthy adults’ calcium intake and screened their hearts for calcium deposits associated with atherosclerosis over 10 years. They found that people who got their calcium from food had a lower risk of atherosclerosis, while calcium supplements were associated with an increased risk of atherosclerosis.

The NIH recommends 1,000 mg of calcium a day for women ages 19 to 50 and 1,200 mg a day for women 51 and older. The recommendation for men ages 19 to 70 is 1,000 mg a day and 1,200 mg a day for men 71 and older. According to the Dietary Guidelines for Americans, there are various food sources of calcium, including plain low-fat yogurt, tofu, nonfat milk, cheese, and fortified cereal and juices.

Calcium deficiency, or hypocalcemia, may be detected by routine blood tests. If you have low calcium blood levels despite having adequate dietary intake, your doctor may prescribe a calcium supplement.

4. Multivitamins and Multiminerals: No Substitute for a Healthy Diet

Think that a healthy lifestyle requires not just good-for-you foods, exercise, and enough sleep but also taking a daily multivitamin-multimineral supplement? When you consider that an estimated one-third of adults in the United States and one-quarter of youths take them, per the NIH, you may be surprised to learn that the jury’s still out on whether they’re helpful.

One study published in the journal JAMA Internal Medicine, which examined data from nearly 40,000 women older than 19 who were part of the Iowa Women’s Health Study, found that, on average, women who took supplementshad a higher risk of early death than women who didn’t take supplements. Multivitamins did little or nothing to protect against common cancers, cardiovascular disease, or death.

Other research has found benefits to taking multivitamins. For example, a study in the August 2017 Nutrients concluded that frequent use of multivitamin and mineral supplements helped prevent micronutrient shortfalls that might otherwise cause health problems.

Overall, research on whether multivitamins actually promote health is mixed.

For women of childbearing age, taking prenatal vitamins with folic acid is recommended by the American College of Obstetricians and Gynecologists to help prevent birth defects. Multivitamins might be prescribed by your doctor if you have malabsorption syndrome, a condition in which the body does not properly absorb vitamins and minerals.

In general, though, Manson says, “a supplement can never be a substitute for a healthy diet.”

Though multivitamins pose a low risk for drug interactions, the NIH recommends that smokers and former smokers avoid taking multivitamins with high levels of vitamin A or beta-carotene because these nutrients may increase the risk for lung cancer when consumed as supplements.

5. Fish Oil Supplements: Choose Fish or Flaxseed Instead

Rich in omega-3 fatty acids, fish oil has been touted as a means to reduce heart disease and other ailments. Yet increasing evidence suggests that fish oil supplements have questionable benefits.

For example, a study published in January 2019 in the New England Journal of Medicine found that omega-3 supplements did nothing to reduce heart attacks, strokes, or deaths from heart disease in middle-aged and older men and women without any known risk factors for cardiovascular disease. An earlier study analyzed people at high risk for cardiovascular disease and also reported no benefit.

Plus, a later review and meta-analysis of 83 randomized controlled trials, which was published in August 2019 in the journal BMJ, revealed that omega-3s, whether in supplement or food form, didn’t reduce type 2 diabetes risk among the 58,000 participants involved.

But it’s not all negative news when it comes to omega-3 supplements: A large randomized controlled trial published in January 2022 in BMJ suggests that fish oil supplements may provide health benefits when combined with vitamin D supplements, though in this case the benefits weren’t statistically significant. The authors observed that this cocktail, as well as vitamin D supplements alone, led to a lower incidence of autoimmune conditions such as psoriasis and rheumatoid arthritis.

Currently, there’s not enough positive evidence for doctors to prescribe fish oil supplements to every patient, though. Aside from the mixed research results, omega-3 deficiency is very rare in the United States, according to the NIH. One important drug interaction with omega-3 supplements is Coumadin (warfarin).

Still, many people fail to consume enough omega-3s in their diet for optimal health. Per the Harvard T.H. Chan School of Public Health, omega-3s play a critical role in the formation of hormones that relax artery walls, reduce inflammation, and aid blood clotting.

The best way to get adequate, and safe, amounts of omega-3s is by eating a variety of foods that are rich in them. The three main types of omega-3s are eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). According to the NIH, the following are some food sources of EPA, DHA, and ALA omega-3s.

EPA and DHA

• Fish and other seafood, especially cold-water fatty fish, such as salmon, mackerel, tuna, herring, and sardines

DHA

• Fortified foods, such as certain brands of eggs, yogurt, juices, milk, and soy beverages (may contain other forms of omega-3s, depending on the brand)

ALA

• Nuts and seeds, such as flaxseed, chia seeds, and walnuts
• Plant oils, such as flaxseed oil, soybean oil, and canola oil

6.

 Kava: Overuse Can Harm Your Liver

Kava is an herb that in concentrated forms has been used to treat general anxiety disorder with some success. A study suggests that the South Pacific plant can be an effective alternative treatment to prescription medication for people diagnosed with generalized anxiety disorder (GAD). An earlier, smaller study also showed that taking kava significantly reduced anxiety compared with a placebo in people with GAD.

But taking too much kava, or taking it for too long, has been linked to serious liver damage, including hepatitis, cirrhosis, and liver failure. As a result, according to the NIH, the FDA has warned that people, especially those with liver disease or liver problems, or those who are taking drugs that can affect the liver, should talk to their healthcare practitioner before using kava. In addition, the National Center for Complementary and Integrative Health reports that heavy consumption of kava has been associated with heart problems and eye irritation.

Several drugs may interact with kava, from anticonvulsants to anti-anxiety medications, and any drug metabolized by the liver, notes Mount Sinai. What’s more, people taking kava need to avoid drinking alcohol due to potential liver harm, the hospital recommends.

7. Soy Isolate: Careful With Estrogen?

Tofu, tempeh, and soy milk are all good plant-based sources of protein, fiber, and other key nutrients, per the Cleveland Clinic. Some women also take soy in supplement form because the plant contains estrogenlike compounds called isoflavones that are thought to relieve symptoms of menopause. Yet some health experts have raised concerns that the isoflavones in soy supplements may contribute to an increased risk of breast cancer.

The good news is that large-scale studies of humans have not shown any increased breast cancer risk from eating whole soy foods, such as tofu and edamame, in moderation, according to Cancer.Net.

Indeed, a study published in March 2017 in the journal Cancer looked at 6,235 breast cancer survivors and linked eating the equivalent of one serving of soybeans a week to a 21 percent lower risk of death from all causes during the nearly 10-year follow-up period.

But not enough research has been done on soy protein isolate (SPI) — the powder formed by removing the protein from the rest of the plant — to know its true effect on breast cancer risk, Millstine says. According to the Mayo Clinic, women with a family history of breast cancer or thyroid health problems may be more vulnerable to these effects. But again, this is theoretical and more studies are needed.

In addition to supplements, SPI is often found in power bars, veggie burgers, and some soups, sauces, smoothies, and breakfast cereals.

The bottom line: While current research suggests that whole-food sources of soy don’t increase breast cancer risk, the jury is still out. Before adding any supplement to your health and wellness regimen, discuss your options with your healthcare team and other health providers to weigh the potential risks and benefits for your individual situation.

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B vitamins ー Benefits and instructions for taking

Vitamins ー is a group of organic compounds essential for normal physiological functioning. However, these compounds are not produced by the body itself (2), but must be supplied through the diet. For life, a person needs 13 vitamins in sufficient quantities. B group vitamins include:

• thiamine;
• riboflavin;
• niacin;
• pantothenic acid;
• pyridoxine;
• folic acid;
• cobalamin.

This grouping was not based on any chemical structural similarity, but rather on their water solubility and the interrelated cellular coenzyme functions they perform (1).

Their synthesis occurs due to plants, the process itself takes place in such plant cell organelles as: chloroplasts, mitochondria and cytosol. Synthesis is carried out depending on what the plant needs for this substance. Vitamin B12, unlike other representatives of this group, is synthesized by bacteria and is usually isolated from animal products. Although most of the compounds are derived from plants, their consumption often occurs at a higher level in the food chain ー in animal products (dairy products, meat, eggs).

B vitamins: importance for the nervous system

The effective functioning of the central nervous system depends to some extent on an adequate and constant supply of essential substances. A number of scientific sources have described and confirmed the impact of a deficiency of B vitamins on neurological and psychological functions. Folic acid, cobalamin, and pyridoxine are water-soluble B vitamins that are involved in a variety of critical metabolic processes in the brain.

The relationship between thiamine deficiency and the development of various deficient conditions has long been studied (3). It is used for a number of physiological processes, in addition to being involved in glucose metabolism, as well as in the synthesis of myelin and several types of neurotransmitters (4). Its main function is that it acts as an important cofactor in the conversion of carbohydrates, which makes it possible to provide energy to the cells of the nervous system. The process of energy metabolism must be constant due to the high costs of brain cells to maintain their functions (5). Participating in maintaining the work of myelin sheaths, it also affects the speed of nerve conduction. In addition, it has an antioxidant, protective effect on the cells of the nervous system. This property of thiamine allows it to prevent cell damage resulting from hyperglycemia.

Pyridoxine is well known for its involvement in the synthesis of neurotransmitters. It acts on the adrenergic, serotonergic and glutamatergic systems. Due to the implementation of the regulation of the functioning of the glutamatergic system, it has a neuroprotective property (6). May be used in the treatment of pyridoxine-dependent seizures, a pathology in young children in which seizures are not relieved by conventional anticonvulsants (7). It is also involved in the process of myelin synthesis. Pyridoxine deficiency is manifested by impaired cognitive functions, the appearance of seizures, depression, carpal tunnel syndrome. Deficiency of thiamine and pyridoxine is rare in healthy individuals in developed countries, but can be detected in patients who are on hemodialysis (8). During pregnancy, more pyridoxine is required to ensure the normal development of the fetal brain. Pyridoxine supplementation reduces nausea in early pregnancy (9).

Cobalamin is known for its integral role in the processes of hematopoiesis, is a coenzyme in many biochemical processes that contribute to the normal functioning of the nervous system. Plays a significant role in myelin synthesis, promotes nerve regeneration after injury (10). The level of cobalamin affects the amount of reduced glutathione with antioxidant functions in erythrocytes and in the liver. With low availability of reduced glutathione in cobalamin deficiency, cells can be subjected to increased oxidative stress. Cobalamin deficiency causes neurological spectrum disorders. Individuals with its deficiency may experience symptoms such as symmetrical dysesthesia, spastic paraparesis or tetraparesis, paresthesias, numbness of the extremities, difficulty writing or buttoning clothes (11). Deficiency is common in the elderly, vegetarians, and vegans.

Some studies suggest that vitamins B1, B6 and B12 may play a synergistic biochemical role in the nervous system and cannot be used interchangeably.

Vitamin B: where it is found

B vitamins play an important role in growth, development and other bodily functions. Food sources of vitamin B, both plant and animal. Vitamin B deficiency can lead to various diseases. With optimal proper nutrition, the required amount of nutrients will be provided with the diet.

Pyridoxine is found in foods such as fish, poultry, nuts, legumes, potatoes and bananas. In clinical studies, it was found that the level of pyridoxine in the blood serum was low in all age groups. This is because some plant foods contain a form of vitamin B6 that has half the bioavailability of vitamin B6 obtained from another source or supplement ( 13Trusted Source ). Thus, it is better to stick to a mixed diet, which has a bioavailability of 75%. Vegetarians and vegans may need to increase their vitamin B6 intake by incorporating foods high in pyridoxine into their diets or taking supplements to make up for the deficiency. To date, neurotoxicity and colorectal cancer associated with the use of pyridoxine at doses above 200 mg remain controversial (14).

Green leafy vegetables are especially rich in folic acid. In addition to them, foods high in folic acid are citrus fruits, legumes, and cereals. Folic acid for use is available both as a single ingredient and in the form of combined products, vitamin B complexes, and multivitamins. Enrichment of flour products with folic acid contributed to a significant reduction in the incidence of congenital defects of the central nervous system, malformations of the skull, and heart defects (15). Women planning pregnancy are advised to take 400 micrograms of folic acid per day to prevent birth defects in the fetus. More than 0.4 mg of folic acid per day has been shown to increase the risk of developing cancer, according to some studies (16). By itself, folic acid is not highly toxic, it is a water-soluble vitamin and is regularly excreted from the body in the urine.

Cobalamin can only be obtained from animal products. Rich foods include liver, beef, lamb, chicken, eggs and dairy products. To date, it is not possible to obtain a bioactive form of cobalamin from plant products. In the course of observations, it was found that some foods contaminated or fermented with bacteria (tempeh, Thai fish sauce) contain vitamin B12, but they can be poorly absorbed. Most people have no difficulty getting the recommended daily allowance for cobalamin. But, people who follow diets that exclude cheese, milk, dairy products and eggs can become deficient at any age ( 17Trusted Source ). It can also be caused by malabsorption, improper or inadequate nutrition, long-term vegetarian or vegan diets. Pregnant and lactating women who follow a vegetarian or vegan diet are especially at high risk due to their increased metabolic requirement for vitamin B12. Vitamin B12 deficiency manifests as megaloblastic anemia. If detected late and not properly treated, cobalamin deficiency can lead to neurological disorders, which, unfortunately, can no longer be corrected (18). Neurological symptoms manifest as numbness and tingling in the arms and legs, difficulty walking, memory impairment, disorientation, and mood changes.

B vitamins for children

Most often, children get the amount of vitamins they need from food. In cases where the child has dietary restrictions or allergic reactions, he may develop a vitamin deficiency that cannot be corrected without nutritional supplements. It is necessary to determine whether the child is getting enough vitamin B by contacting a pediatrician. Deficiency of B vitamins may cause symptoms such as:

• irritability;
• lethargy;
• anxiety;
• retardation of growth and development;
• the appearance of skin rashes.

Side Effects of B Vitamins

Due to the water soluble nature of these vitamins, over-consumption of these compounds is unlikely, even with a B-complex supplement. Supplementation with an excessively high content of B vitamins may cause undesirable effects. High doses of niacin have been associated with vomiting, elevated blood sugar levels, flushing of the skin, and liver damage (19). High doses of pyridoxine can cause nerve damage, photophobia, and skin lesions (20). The use of a vitamin B complex can cause the urine to turn bright yellow, but this is not a dangerous condition and indicates the excretion of substances in excess by the body.

How to take vitamins of group B

The best option would be to take them with your daily diet. However, in the presence of a deficiency, vitamin complexes should be used at a dose prescribed by a doctor. The drugs are taken in a course, continuous use is impractical, since the substances will accumulate in the body, and then their excess will be excreted in the urine. Compounds of this group are widely represented in the form of a multivitamin complex in various dosage forms. Children need to buy children’s drugs and use them in the dosage that was prescribed by the pediatrician. Vitamins are usually taken with food once a day.

Conclusion

A total of 8 types of vitamin B are known, each of them performs a specific function in the human body, so they are important and not interchangeable. When they are deficient, various symptoms appear 12. Most people in developed countries can get the necessary nutrients through the food they eat. However, if vitamin deficiency is still present, supplementation should be considered.

Literature

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why you can’t drink them just like that and how it can end

Most people assume that too much vitamins can’t hurt. But no sane person would take an antibiotic without being sick. For some reason, many people take supplements despite the fact that their body is not suffering from a deficiency. In most cases, this is just a waste of money, and extra vitamins are simply washed out of the body. But a large amount of unnecessary substances leads to dangerous and sometimes irreversible consequences. Hi-Tech analyzed the effect of various groups of vitamins on the human body and found out what diseases are caused by their overdose.

Read Hi-Tech in

Vitamins are organic compounds needed in small amounts to sustain life. Nutrition experts say that people only need the recommended daily allowance, the amount found in a typical balanced diet. Manufacturers claim that the usual diet does not contain enough vitamins, and the more you take, the better. But modern research shows that additives cause not only temporary negative effects on human health, but can also provoke serious illness, up to death.

B vitamins

People used to think B vitamins were harmless because, like vitamin C, they are water-soluble and cannot be stored in the body like fat-soluble A, D, E, and K. However, scientists have now determined that that excessive consumption of certain B vitamins causes serious health problems.

For example, vitamin B6 (pyridoxine) can cause neurodegenerative changes even at slightly higher than the recommended dose for a long time. Higher doses of B6 accumulate in the body and cause damage to nerve endings, causing numbness and tingling in the limbs, which can eventually become irreversible. Too much causes increased sensitivity to sunlight, resulting in skin rashes, nausea, vomiting, chronic abdominal pain, loss of appetite, and impaired liver function.

High doses of vitamin B3 (niacin) also cause problems when exceeding 2-3 g per day to lower cholesterol levels. Reactions range from redness, itching, nervousness and headache to intestinal cramps. Those who exceed the recommended dose of niacin may experience nausea, jaundice, elevated liver enzymes, and a toxic picture that mimics hepatitis. Symptoms disappear when niacin is discontinued. Lean meats, milk, eggs, whole grain breads and cereals, nuts, leafy green vegetables, and protein foods are the best natural sources of niacin. With a balanced diet, there is no need for its additional intake.

In humans, vitamin B12 plays a role in metabolism, red blood cell formation, and maintenance of the central nervous system. According to a 2015 study, an overdose of B12 can contribute to acne. The study showed that upon contact with it, the skin bacteria P.acnes, with the help of porphyrin, begin to activate the process leading to acne inflammation. This is a key step in the later stages of acne development.

Huiying Li, co-author of the study and assistant professor of pharmacology at the David Geffen School of Medicine at UCLA, says the connection is clear. Her team decided to conduct an experiment that clearly, at the molecular level, demonstrates the detrimental effect of the vitamin. “There is still a lot to be learned to understand whether B12 actually causes acne,” says Lee. She also warned that it is too early to tell people who have problems with breakouts should stop taking multivitamins with B12. The scientist noted that most of the studies that found an increase in inflammation associated with taking the vitamin involved a single injection with large doses.

Vitamin C

At the right dose, vitamin C neutralizes charged free radicals by accepting their free electron. This is a real “molecular martyr”, taking a hit on himself to protect the cellular neighborhood.

But by accepting an electron, vitamin C itself becomes a free radical capable of damaging cell membranes, proteins and DNA. As food chemist William Porter wrote in 1993, “Vitamin C is really two-faced Janus, Dr. Jekyll is Mr. Hyde, an oxymoron for antioxidants.” Chemical pathologists at the University of Leicester found in a six-week study of 30 healthy men and women that a daily 500 mg vitamin C supplement had a pro-oxidant as well as an antioxidant effect on the DNA of the genetic material. Researchers have found that at 500mg levels, vitamin C promotes genetic damage by free radicals to part of the DNA, the adenine bases.

The results, published in Nature, confirm decades of warnings by American physician Dr. Victor Herbert, professor of medicine at Mount Sinai School of Medicine in New York. Herbert showed, primarily through laboratory studies, that vitamin C supplements promote the production of iron free radicals in the body.

“Vitamin C supplements mobilize harmless iron stored in the body and convert it into iron that causes damage to the heart and other organs,” says Dr. Herbert. “Unlike the vitamin found naturally in foods like orange juice, as a supplement it is not an antioxidant. It is a redox agent—an antioxidant in some circumstances and a pro-oxidant in others. ”

Many people think that vitamin C helps prevent colds. Despite studies around the world, there is still no conclusive evidence to support this. Some experiments have shown that taking large doses of vitamin C (more than 1,000 mg per day) continuously or at the first sign of a cold can reduce some symptoms and their duration – making them about half a day shorter. And that doesn’t stop the cold at all.

Large doses may cause nausea, abdominal cramps, headaches, fatigue, kidney stones and diarrhea. It can also affect the body’s ability to process (metabolize) other nutrients, such as causing iron levels to spike.

Too much vitamin C in the body can also affect medical tests such as diabetes. Adults need about 45 mg of vitamin C per day. However, almost any excess amount is rapidly excreted from the body.

Vitamin E

Vitamin E is often referred to as a potential fountain of youth. However, there is no evidence that taking large doses can either stop or reverse the signs of aging. None of the vitamins can restore sexual desire or cure infertility.

In a study published in the New England Journal of Medicine in 1994, 29,000 Finnish men, all smokers, received daily vitamin E, beta-carotene, both, or placebo. The study found that those who took beta-carotene for five to eight years were more likely to die from lung cancer or heart disease.

Two years later, another study on vitamin supplementation was published in the same journal. In it, 18,000 people who had a history of increased risk of lung cancer due to exposure to chemicals or smoking received a combination of vitamin A and beta-carotene or a placebo. The researchers stopped the experiment when they found that those who took the vitamins had a 46% higher risk of dying from lung cancer.

Then, in 2004, the SELECT study (Selenium and Vitamin E Cancer Prevention Study – Hi-Tech) was developed to determine the long-term effects of selenium and vitamin E supplementation on prostate cancer. Previous experiments have hinted that both of these substances may provide protection against prostate cancer. But the study showed a 17 percent increase in the risk of developing prostate cancer in men who took 400 units of vitamin E daily. One group took 400 international units of vitamin E per day, the second received 200 micrograms of selenium per day, the third received both vitamin E and selenium, and the fourth received only an inactive placebo.

All men were 50 years of age or older and had no early signs of prostate cancer as evidenced by digital rectal examination and PSA levels. The experiment began in August 2001 and ended in June 2004.

Preliminary study results showed an increase in the incidence of prostate cancer in both the vitamin E and selenium groups. Although this increase was not statistically significant, the increase in the vitamin E group was almost the same. The trial aimed to test the protective effect of vitamin E or selenium, but found only evidence of possible harm.

Another review published in 2005 in the Annals of Internal Medicine found that in 19 trials involving almost 136,000 people, vitamin E supplementation increased the risk of premature death. In people with vascular disease or diabetes, it increased the risk of heart failure.

Vitamin A

Vitamin A is known to help maintain good vision, healthy skin, teeth, skeletal and soft tissues, mucous membranes. People who do not get enough vitamin A are more likely to develop infectious diseases and eye problems.

But a high dose of the vitamin causes nausea, vomiting, diarrhea, loss of appetite, fatigue, headaches, dizziness, blurred vision, poor muscle coordination, itching and peeling of the skin, bone pain, hair loss, irregular menstruation in women, osteoporosis and temporary or permanent liver damage. High doses of vitamin A also increase the risk of lung cancer in smokers. The problem with it is that, unlike other vitamins, excess amounts don’t get washed out in the urine, but rather accumulate in the liver.

Acute vitamin A hypervitaminosis was first documented in Arctic explorers who unknowingly consumed vitamin A-rich livers from many arctic animals—seals, huskies, and even polar bears. The symptoms of this extremely unpleasant condition among scientists were hair loss, damage to the skin and liver, hemorrhage, coma and death.

In November 1912, a group of three men and 16 dogs set out from a remote base in East Antarctica to investigate a series of cracks in the ice.

Three months later, only one of the men returned. His name was Douglas Mawson. His skin was flaking and his hair was falling out. He lost almost half his weight. He said that Sir Edmund Hillary called this expedition “the greatest story of survival in the history of polar exploration. ”

After a month of travel, one member of the team, along with a tent, provisions and six dogs, fell into a crevice. Mawson and his colleague Xavier Merz decided to return to base, surviving by eating the remaining dogs. A few weeks later, Merz developed severe abdominal pain. Then his skin began to peel off and his hair fell out. He died of dehydration in delirium a few days later.

Mawson had similar symptoms but managed to survive despite starvation and lack of vital nutrients. Mawson’s description of his symptoms is almost a textbook description of a vitamin A overdose, probably from eating a dog’s liver. Just 100 grams of husky liver can give a hungry researcher a lethal dose.

Arctic Expedition with Douglas Mawson

Vitamin D

Our genetics influence vitamin D levels. We can use this information to determine if a low amount really increases the risk of disease (rather than being a consequence of it). So far, the available evidence suggests that low vitamin D levels are either irrelevant or only a marker of the disease. But studies over the past five years have shown that even fortified vitamin D and calcium supplements, and their ineffectiveness in preventing fractures, can increase the risk of heart disease.

While several studies in normal people found no protective effects from vitamin D, others were more worrying. One 2015 randomized trial of 409 elderly people in Finland found that it did not offer any benefit over placebo or exercise, and that the fracture rate was actually somewhat higher.

The usual prescribed dose in most countries is 800 to 1,000 units per day (ie 24,000 to 30,000 units per month). However, two randomized trials found that 40,000 to 60,000 units of vitamin D per month actually becomes a dangerous substance.

A study of more than 2,000 older Australians found that patients who received high doses until blood levels of vitamin D were within the optimal range only experienced a 20% to 30% increase in fractures and falls compared to those who received low doses or did not reach “optimum blood levels”.

Why vitamin D supplements are often harmful is more difficult to explain. Some people who do not take supplements have naturally high blood levels of the vitamin. This could be because they spend a lot of time in the sun or regularly eat oily fish – and there is no evidence that this is harmful. Above average levels may also be due to genes that, on average, account for about 50% of the differences between people. Thus, doctors’ obsession with trying to get everyone up to standard normal blood levels is as unprofessional as a one-size-fits-all approach to diet.

Calcium

Calcium is an important nutrient for bone health, but new research shows that older women who take high doses of this substance are at risk of cardiovascular disease, which can be fatal.

Swedish researchers followed 61,433 women born between 1914 and 1948 for an average of 19 years, noting the causes of their death. The scientists also used questionnaires to record the intake of various calcium supplements. After adjusting for indicators of physical activity, bad habits, and dietary factors, they found that women who consumed 1,400 mg or more of calcium per day had twice the risk of cardiovascular disease compared with those who took 600 to 1,000 mg. These women also showed up on 49% higher mortality from cardiovascular diseases and 40% higher deaths from any cause.

The authors note that calcium may increase blood protein levels associated with an increased risk of cardiovascular disease.

“If you have a normal diet, you don’t need to take calcium supplements,” said Dr. Karl Mikaelsson, professor and orthopedic surgeon at Uppsala University in Sweden. “Calcium supplements are useful if you have a very low intake of calcium, but only a doctor can calculate the exact dosage.”

Iron

Anemia is a medical condition that occurs when a person does not have enough healthy red blood cells to supply enough oxygen to your tissues. It is common in women and can cause fatigue and a feeling of weakness.

Taking iron supplements without the dose recommended by the doctor is extremely fraught. Unnecessary iron builds up in the body and can even rise to toxic levels. Taking more iron causes skin discoloration, an enlarged liver or spleen, abdominal pain, congestive heart failure, irregular heart rhythm, and insulin-dependent diabetes.

Excessive amounts of iron are especially common in pregnant women. A recent study by a group of physicians in India found that an excessive dose of iron in healthy, non-anemic women can lead to problems such as low birth weight, preterm labor, and poor baby growth during the uterus.

Why is it dangerous?

Antioxidants’ fight against oxidation sounds like a fight between good and evil from the lips of the pharmaceutical companies. Oxidation occurs in cellular organelles called mitochondria, where the body converts food into energy, a process that requires oxygen. One of the consequences of oxidation is the generation of free radicals. They can damage DNA, cell membranes, and the lining of arteries; not surprisingly, they have been linked to aging, cancer, and heart disease.

To neutralize free radicals, the body produces antioxidants. Antioxidants can also be obtained from fruits and vegetables, especially selenium, beta-carotene, and vitamins A, C, and E. Some studies have shown that people who eat more fruits and vegetables have lower rates of cancer and heart disease and live longer. The logic is obvious. If fruits and vegetables contain antioxidants and people who eat fruits and vegetables are healthier, then those who take supplemental antioxidants should also be healthier. But it doesn’t work.

A likely explanation is that free radicals are not as bad as they are made out to be. (In fact, people need them to kill bacteria and destroy new cancer cells.) And when people take large doses of antioxidants in the form of supplemental vitamins, the balance between free radical production and destruction can shift too much in one direction, causing an unnatural state where the immune system stops working properly.