Omega-3 fatty acids have been touted for warding off strokes and other cardiovascular events. And antioxidants such as vitamins C and E and beta carotene were seen as promising silver bullets against heart disease, cancer, and even Alzheimer's disease.

Here's the big caveat: many of those exciting supplement studies were observational—they didn't test a particular supplement against a placebo inactive pill in a controlled setting. The results of more stringent randomized controlled trials haven't yielded the same good news. And when the rigorous evidence is available from randomized controlled trials, often the results are at odds with the findings of the observational studies," explains Dr.

JoAnn Manson, chief of preventive medicine at Brigham and Women's Hospital, professor of medicine at Harvard Medical School, and principal investigator of a large randomized trial known as VITAL Vitamin D and Omega-3 Trial.

Because observational studies may not fully control for dietary factors, exercise habits, and other variables, they can't prove whether the treatment is responsible for the health benefits. Manson says. Some supplements that were found to have health benefits in observational studies turned out, with more rigorous testing, to be not only ineffective but also risky.

Vitamin E, which was initially thought to protect the heart, was later discovered to increase the risk for bleeding strokes. Folic acid and other B vitamins were once believed to prevent heart disease and strokes—until later studies not only didn't confirm that benefit but actually raised concerns that high doses of these nutrients might increase cancer risk.

We need a variety of nutrients each day to stay healthy, including calcium and vitamin D to protect our bones, folic acid to produce and maintain new cells, and vitamin A to preserve a healthy immune system and vision.

Yet the source of these nutrients is important. Fruits, vegetables, fish, and other healthy foods contain nutrients and other substances not found in a pill, which work together to keep us healthy.

We can't get the same synergistic effect from a supplement. Taking certain vitamins or minerals in higher-than-recommended doses may even interfere with nutrient absorption or cause side effects.

Before you take any supplements for disease prevention, it's important to know whether the potential benefits outweigh the risks.

To make that conclusion, you need to look at the results of well-designed studies. A recent randomized trial in men suggested multivitamins have possible benefits for cancer prevention.

For many of the other popular supplements, including vitamin D and omega-3 fatty acids, results from randomized controlled trials should be available within the next five years, according to Dr.

Until then, be judicious about your use of supplements. If you're lacking in a particular nutrient, ask your doctor whether you need to look beyond your diet to make up for what you're missing—but don't take more than the recommended daily intake for that nutrient unless your health care provider advises it.

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Recent Blog Articles. Flowers, chocolates, organ donation — are you in? What is a tongue-tie? Prenatal vitamins are dietary supplements commonly given to pregnant women to supply nutrients that may reduce health complications for the mother and fetus.

Although prenatal vitamins are not meant to substitute for dietary nutrition, prenatal supplementation may be beneficial for pregnant women at risk of nutrient deficiencies because of diet limitations or restrictions.

The most common components in prenatal vitamins include vitamins B 6 , folate , B 12 , C , D , E , iron and calcium. Sufficient intake of vitamin B 6 can lower the risk of early pregnancy loss and relieve symptoms of morning sickness. Iron supplementation can lower the risk of iron deficiency anemia for pregnant women.

Individuals with hypokalemic sensory overstimulation are sometimes diagnosed as having attention deficit hyperactivity disorder ADHD , raising the possibility that a subtype of ADHD has a cause that can be understood mechanistically and treated in a novel way. The sensory overload is treatable with oral potassium gluconate.

A study on herbal supplements found that many products were of low quality, one third did not contain the active ingredient s claimed, and one third contained unlisted substances. The test involves looking for DNA fragments from the plants named as the dietary supplement ingredients in the products.

One scientist said that it was possible that the extraction process used to create the supplements removed or destroyed all DNA.

This, however, would not explain the presence of DNA from plants such as rice or wheat, that were not listed as ingredients. A study of dietary supplements sold between and identified that contained unlisted pharmaceutical drugs , many of which could interact with other medications and lead to hospitalization.

Muscle building supplements were contaminated with anabolic steroids that can lead to health complications affecting the kidney, the heart, and cause gynecomastia.

Despite these findings, fewer than half of the adulterated supplements were recalled. The European Commission has published harmonized rules on supplement products to assure consumers have minimal health risks from using dietary supplements and are not misled by advertising.

In the United States and Canada, dietary supplements are considered a subset of foods, and are regulated accordingly. Food and Drug Administration FDA monitors supplement products for accuracy in advertising and labeling. Dietary supplements are regulated by the FDA as food products subject to compliance with current Good Manufacturing Practices CGMP and labeling with science-based ingredient descriptions and advertising.

Federal Trade Commission , which litigates against deceptive advertising in marketed products, [] established a consumer center to assist reports of false health claims in product advertising for dietary supplements. In the United States, manufacturers of dietary supplements are required to demonstrate safety of their products before approval is granted for commerce.

Among general reasons for the possible harmful effects of dietary supplements are: a absorption in a short time, b manufacturing quality and contamination, and c enhancing both positive and negative effects at the same time.

Work done by scientists in the early 20th century on identifying individual nutrients in food and developing ways to manufacture them raised hopes that optimal health could be achieved and diseases prevented by adding them to food and providing people with dietary supplements; while there were successes in preventing vitamin deficiencies , and preventing conditions like neural tube defects by supplementation and food fortification with folic acid , no targeted supplementation or fortification strategies to prevent major diseases like cancer or cardiovascular diseases have proved successful.

For example, while increased consumption of fruits and vegetables are related to decreases in mortality, cardiovascular diseases and cancers, supplementation with key factors found in fruits and vegetable, like antioxidants , vitamins, or minerals, do not help and some have been found to be harmful in some cases.

As a result of the lack of good data for supplementation and the strong data for dietary pattern, public health recommendations for healthy eating urge people to eat a plant-based diet of whole foods, minimizing ultra-processed food , salt and sugar and to get exercise daily, and to abandon Western pattern diets and a sedentary lifestyle.

The regulation of food and dietary supplements by the U. Food and Drug Administration FDA is governed by various statutes enacted by the United States Congress. Pursuant to the Federal Food, Drug, and Cosmetic Act and accompanying legislation, the FDA has authority to oversee the quality of substances sold as food in the United States, and to monitor claims made in the labeling about both the composition and the health benefits of foods.

Substances which the FDA regulates as food are subdivided into various categories, including foods, food additives , added substances man-made substances which are not intentionally introduced into food, but nevertheless end up in it , and dietary supplements.

The specific standards which the FDA exercises differ from one category to the next. Furthermore, the FDA has been granted a variety of means by which it can address violations of the standards for a given category of substances. Dietary supplement manufacture is required to comply with the good manufacturing practices established in The FDA can visit manufacturing facilities, send Warning Letters [] if not in compliance with GMPs, stop production, and if there is a health risk, require that the company conduct a recall.

The European Union 's EU Food Supplements Directive of requires that supplements be demonstrated to be safe, both in dosages and in purity.

As a category of food, food supplements cannot be labeled with drug claims but can bear health claims and nutrition claims. The dietary supplements industry in the United Kingdom UK , one of the 28 countries in the bloc, strongly opposed the Directive.

In addition, a large number of consumers throughout Europe, including over one million in the UK, and various doctors and scientists, had signed petitions by against what are viewed by the petitioners as unjustified restrictions of consumer choice.

Although the European Court of Justice's Advocate General subsequently said that the bloc's plan to tighten rules on the sale of vitamins and food supplements should be scrapped, [] he was eventually overruled by the European Court, which decided that the measures in question were necessary and appropriate for the purpose of protecting public health.

ANH, however, interpreted the ban as applying only to synthetically produced supplements, and not to vitamins and minerals normally found in or consumed as part of the diet.

They also said that any refusal to add the product to the list must be open to challenge in the courts. During the COVID pandemic in the United States, the FDA and Federal Trade Commission FTC warned consumers about marketing scams of fraudulent supplement products, including homeopathic remedies , cannabidiol products , teas, essential oils , tinctures and colloidal silver , among others.

Products that claim to cure, mitigate, treat, diagnose or prevent disease, but are not proven safe and effective for those purposes, defraud consumers of money and can place consumers at risk for serious harm" [] [] [].

Examples of ongoing government research organizations to better understand the potential health properties and safety of dietary supplements are the European Food Safety Authority , [3] the Office of Dietary Supplements of the United States National Institutes of Health , [7] [] the Natural and Non-prescription Health Products Directorate of Canada, [] and the Therapeutic Goods Administration of Australia.

As continual research on the properties of supplements accumulates, databases or fact sheets for various supplements are updated regularly, including the Dietary Supplement Label Database, [5] Dietary Supplement Ingredient Database, [] and Dietary Supplement Facts Sheets of the United States.

In , the Australian Government's Department of Health published the results of a review of herbal supplements to determine if any were suitable for coverage by health insurance.

To assure supplements have sufficient quality, standardization, and safety for public consumption, research efforts have focused on development of reference materials for supplement manufacturing and monitoring.

In the United States, the National Health and Nutrition Examination Survey NHANES has investigated habits of using dietary supplements in context of total nutrient intakes from the diet in adults and children.

Limited human research has been conducted on the potential for dietary supplementation to affect disease risk. A academic review indicated a rising incidence of liver injury from use of herbal and dietary supplements, particularly those with steroids , green tea extract , or multiple ingredients.

The potential benefit of using essential nutrient dietary supplements to lower the risk of diseases has been refuted by findings of no effect or weak evidence in numerous clinical reviews, such as for HIV , [] or tuberculosis. A review of clinical trials registered at clinicaltrials.

gov , which would include both drugs and supplements, reported that nearly half of completed trials were sponsored wholly or partially by industry. Improving public information about use of dietary supplements involves investments in professional training programs, further studies of population and nutrient needs, expanding the database information, enhancing collaborations between governments and universities, and translating dietary supplement research into useful information for consumers, health professionals , scientists, and policymakers.

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Download as PDF Printable version. In other projects. Wikimedia Commons. Product providing additional nutrients. For food additions that alter the flavor, color or longevity of food, see Food additive. This article is about supplemental nutrients and similar substances. For herbal medicine, see Herbal supplement.

The examples and perspective in this article may not represent a worldwide view of the subject. You may improve this article , discuss the issue on the talk page , or create a new article , as appropriate. April Learn how and when to remove this template message.

Main article: Vitamin. Main article: Mineral nutrient. Main articles: Protein nutrient and Amino acid. This section is an excerpt from Bodybuilding supplement. Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding , weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass.

Bodybuilding supplements may contain ingredients that are advertised to increase a person's muscle, body weight, athletic performance, and decrease a person's percent body fat for desired muscle definition. Among the most widely used are high protein drinks , pre-workout blends, branched-chain amino acids BCAA , glutamine , arginine , essential fatty acids , creatine , HMB , whey protein , ZMA , and weight loss products.

Main article: Essential fatty acids. Main article: Natural product. See also: Phytochemical , Herbalism , and Traditional Chinese medicine. Main article: Probiotic. Main article: Fertility.

Main article: Prenatal vitamins. Main article: Regulation of food and dietary supplements by the U. Food and Drug Administration. Encyclopædia Britannica. Retrieved 18 February Office of Dietary Supplements, US National Institutes of Health.

Archived from the original on 14 August Retrieved 2 February European Food Safety Authority, European Commission. Grand View Research. San Francisco, CA. Retrieved Retrieved 3 October Office of Dietary Supplement Programs, Center for Food Safety and Applied Nutrition, U. Department of Health and Human Services.

Archived from the original PDF on 18 November May Dietary supplements a framework for evaluating safety. Washington, D. ISBN NY: Avery Group, 3, ISBN Current Genomics.

doi : PMC PMID Preventive Services Task Force". Annals of Internal Medicine. EFSA Journal. Archived from the original on 26 November Archived from the original on October The American Journal of Clinical Nutrition.

International Journal of Food Sciences and Nutrition. S2CID International Olympic Committee. Archived from the original PDF on Sports Medicine. Journal of the American College of Nutrition. April Frontiers in Pharmacology. Institute of Medicine.

National Academy Press. International Journal of Sport Nutrition and Exercise Metabolism. Journal of Applied Physiology. International Journal of Sport Nutrition. March British Journal of Sports Medicine.

Food Processing. The Annals of Thoracic Surgery. American Heart Journal. ISSN US National Institutes of Health, Office of Dietary Supplements. Retrieved 5 April Understanding Nutrition 11th ed. California: Thomson Wadsworth. Archived PDF from the original on August 28, Institute of Medicine, National Academies.

Current Cardiology Reports. January JAMA Internal Medicine. Cochrane Neonatal Group March The Cochrane Database of Systematic Reviews. European Food Safety Authority. Retrieved 1 February Herbal Supplement Sales Up 7.

Nutritional Outlook. Government of Canada. Archived from the original on 18 August Complementary Therapies in Medicine.

PLOS Genetics. Nutraceuticals World. Retrieved 25 September Natural Products Insider. Food Safety Authority of Ireland. Archived from the original on 10 July Retrieved 4 February The British Journal of Nutrition. BMC Medical Ethics. Cochrane IBD Group April Clinical Infectious Diseases.

Advances in Nutrition. Cochrane Gynaecology and Fertility Group August JBRA Assisted Reproduction. Nutrition Reviews. Cochrane Pregnancy and Childbirth Group December Cochrane Pregnancy and Childbirth Group September Archived from the original on March 30, Archived from the original on July 30, Cochrane Pregnancy and Childbirth Group July Archived from the original on January 2, Government Accountability Office 18 March Dietary Supplements: FDA May Have Opportunities to Expand Its Use of Reported Health Problems to Oversee Products Report.

Government Accountability Office, US Government.

You may also submit a report directly to FDA by calling FDA or completing an online form. You should also report your reaction to the manufacturer by using the contact information on the product label.

FDA has established Good Manufacturing Practices GMPs that companies must follow to help ensure the identity, purity, strength, and composition of their dietary supplements.

These GMPs can prevent adding the wrong ingredient or too much or too little of the correct ingredient and reduce the chance of contamination or improper packaging and labeling of a product.

FDA periodically inspects facilities that manufacture supplements. Several independent organizations offer quality testing and allow products that pass these tests to display a seal of quality assurance that indicates the product was properly manufactured, contains the ingredients listed on the label, and does not contain harmful levels of contaminants.

These seals do not guarantee that a product is safe or effective. They can help you determine which supplements, if any, might be valuable for you. Keep a complete record of any dietary supplements and medicines you take.

The Office of Dietary Supplements website has a useful form, My Dietary Supplement and Medicine Record , that you can print and fill out at home. For each product, note the name, the dose you take, how often you take it, and the reason for use. Dietary supplements are products intended to supplement the diet.

They are not medicines and are not intended to treat, diagnose , mitigate , prevent, or cure diseases. FDA is the federal agency that oversees both supplements and medicines, but FDA regulations for dietary supplements are different from those for prescription or over-the-counter medicines.

Medicines must be approved by FDA before they can be sold or marketed. Supplements do not require this approval. Supplement companies are responsible for having evidence that their products are safe, and the label claims are truthful and not misleading.

However, as long as the product does not contain a new dietary ingredient one introduced since October 15, , the company does not have to provide this safety evidence to FDA before the product is marketed. Dietary supplement labels may include certain types of health-related claims.

Manufacturers are permitted to say, for example, that a supplement promotes health or supports a body part or function like heart health or the immune system. This product is not intended to diagnose, treat, cure, or prevent any disease. Manufacturers must follow GMPs to ensure the identity, purity, strength, and composition of their products.

If FDA finds a dietary supplement to be unsafe, it may remove the product from the marketplace or ask the manufacturer to voluntarily recall the product. FDA monitors the marketplace for potential illegal products that may be unsafe or make false or misleading claims.

The Federal Trade Commission , which monitors product advertising, also requires information about a supplement product to be truthful and not misleading. The federal government can take legal action against companies and websites that sell dietary supplements when the companies make false or deceptive statements about their products, if they promote them as treatments or cures for diseases, or if their products are unsafe.

National Institutes of Health NIH supports research and provides educational materials on dietary supplements. FDA issues rules and regulations and oversees dietary supplement labeling, marketing, and safety.

Recall notices are also posted on the FDA webpage or you can subscribe to receive FDA notices of recalls, market withdrawals, and safety alerts.

FTC regulates health and safety claims made in advertising for dietary supplements. USDA provides information on a variety of food and nutrition topics.

HHS provides wellness information, personal health tools, and health news. This fact sheet by the National Institutes of Health NIH Office of Dietary Supplements ODS provides information that should not take the place of medical advice. We encourage you to talk to your health care providers doctor, registered dietitian, pharmacist, etc.

Some of the most popular herbs include:. Talk to your doctor before you begin taking a dietary supplement. He or she can tell you the benefits and risks of each supplement. Make sure he or she knows about anything you already take.

This includes all medicines, both prescription and over-the-counter. Read the ingredient list on supplements to make sure you know what else is in them.

He or she can help you decide which micronutrients you need. Your doctor also can recommend a dietary supplement. This will depend on your overall health and lifestyle. Supplements can cause problems with cancer treatments or surgery.

Your doctor will know if they interact with any health conditions you have. For instance, foods rich in vitamin E and beta-carotene are healthy.

However, the U. Preventive Services Task Force USPSTF and the American Academy of Family Physicians AAFP recommend against taking vitamin E or beta-carotene for the prevention of cardiovascular disease and cancer. People who smoke or are at risk for lung cancer also should avoid beta-carotene.

It can increase their risk of lung cancer. Medicine companies follow FDA regulations. Some makers of dietary supplements follow the U. Pharmacopeial USP Convention quality standards. This means they volunteer to have their products tested.

These supplements display additional credentials on their labels. com Approved Quality. This is especially true for the fat-soluble vitamins A and E. Check the recommended daily allowance RDA on the label. Taking too much can cause unwanted or harmful side effects.

However, some herbal supplements may not be safe. They could contain unlisted ingredients that make you sick. Products may even contain toxic, or poisonous, substances. Examples include arsenic, mercury, lead, and pesticides.

Supplements must be recalled if they are found to contain toxic ingredients. National Institutes of Health, MedlinePlus: Dietary Supplements. Pharmacopeial USP Convention: Quality Supplements. Last Updated: September 14, This information provides a general overview and may not apply to everyone.

Talk to your family doctor to find out if this information applies to you and to get more information on this subject. Calcium keeps your bones and teeth healthy and strong. Visit The Symptom Checker. Read More. Vitamins and Minerals: How to Get What You Need.

How to Get More Fiber in Your Diet. Diabetes and Nutrition. Antioxidants: What You Need to Know. Nutrition Tips for Kids. Preventing Malnutrition in Older Adults. Nutrition: How to Read a Nutrition Facts Label. Home Prevention and Wellness Food and Nutrition Nutrients and Nutritional Info Dietary Supplements: What You Need to Know.

Path to improved health Vitamins and minerals are known as micronutrients. People who may benefit from multivitamins include: Women who are pregnant or trying to get pregnant.

Women who are breastfeeding. Women who have heavy menstrual periods.