Food

Dietary Supplements: What You Need to Know

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You've heard about them, have probably used them, and have even recommended them to friends or family. But how much do you really know about dietary supplements?

Yes, some can be beneficial to your health — but taking supplements can also involve health risks. Read on for important information for you and your family about dietary supplements.

Some Common Dietary Supplements:

  • Acidophilus
  • Echinacea
  • Fiber
  • Ginger
  • Glucosamine and/or Chonodroitin Sulphate
  • Minerals
  • Omega-3 Fatty Acids
  • St. John's Wort
  • Saw Palmetto
  • Vitamins 

Note: These examples do not represent either an endorsement or approval by FDA.


Q. What are dietary supplements?

A. Dietary supplements include vitamins, minerals, and other less familiar substances — such as herbals, botanicals, amino acids, and enzymes (see box at right). Dietary supplements are also marketed in forms such as tablets, capsules, softgels, and gelcaps. While some dietary supplements are fairly well understood, others need further study.

Q. What are the benefits of dietary supplements?

A. Some supplements may help to assure that you get an adequate dietary intake of essential nutrients. However, supplements should not replace the variety of foods that are important to a healthful diet — so, be sure you eat a variety of foods as well.

Unlike drugs, supplements are not intended to treat, diagnose, prevent, or cure diseases. That means supplements should not make claims, such as "reduces arthritic pain" or "treats heart disease." Claims like these can only legitimately be made for drugs, not dietary supplements.

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Q. Are there any risks in taking supplements?

A. Yes. Many supplements contain active ingredients that have strong biological effects in the body. This could make them unsafe in some situations and hurt or complicate your health. For example, the following actions could lead to harmful — even life-threatening — consequences.

  • Using supplements with medications (whether prescription or over-the-counter)
  • Substituting supplements for prescription medicines
  • Taking too much of some supplements, such as vitamin A, vitamin D, and iron

Some supplements can also have unwanted effects before, during, and after surgery. So, be sure to inform your health-care provider, including your pharmacist, about any supplements you are taking — especially before surgery.

Q. Who's responsible for the safety of dietary supplements?

A. Dietary supplements are not approved by the government for safety and effectiveness before they are marketed. If the dietary supplement contains a NEW ingredient, that ingredient will be reviewed by FDA (not approved) prior to marketing — but only for safety, not effectiveness.

The manufacturers and distributors of dietary supplements are responsible for making sure their products are safe BEFORE they go to market. Manufacturers are required to produce dietary supplements to minimum quality standards and ensure that they do not contain contaminants or impurities, and are accurately labeled.

Manufacturers are required to report all serious dietary supplement related adverse events or illnesses to FDA as of December 2007.

FDA can take dietary supplements off the market if they are found to be unsafe, adulterated, or if the claims on the products are false and misleading.

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Q. What should I do if I have a reaction to a dietary supplement?

A. You, your health-care provider, or anyone else should report a serious problem from the use of any dietary supplement directly to FDA's MedWatch Program at:

1-800-FDA-1088
(toll-free phone number)

1-800-FDA-0178
(fax)

The FDA Safety Information and Adverse Event Reporting Program

FDA would like to know whenever the use of a dietary supplement causes you to have a serious reaction or illness, even if you're not certain that the product was the cause, and/or you did not visit a doctor or clinic.

Q. How can I find out more about the dietary supplement I'm taking?

A. If you want to know more about the product you are taking, check with the manufacturer or distributor about:

  • Information to support the claims of the product
  • Information on the safety and effectiveness of the ingredients in the product
  • Any reports of adverse effects or events from consumers using the product

Q. How can I be a smart supplement shopper?

A. Although the benefits of some dietary supplements have been documented, the claims of others may be unproven. If something sounds too good to be true, it usually is. Be a savvy supplement user. Here's how:

  • Watch out for false statements like: 
    • A quick and effective "cure-all"
    • Can treat or cure diseases
    • "Totally safe" or has "no side effects"
  • Be aware that the term natural doesn't always mean safe.
  • Don't assume that even if a product may not help you, at least it won't hurt you.
  • When searching for supplements on the Web, use the sites of respected organizations, rather than doing blind searches.
  • See Health Fraud Scams for general information on fraudulent dietary supplements.
  • See the FDA's Tainted Supplements page for a list of some of the potentially hazardous dietary supplements marketed to consumers.
  • Ask your health-care provider for help in distinguishing between reliable and questionable information.
  • Always remember — safety first!

Before making decisions about whether to take a supplement, see your health-care provider or a registered dietitian. They can help you achieve a balance between the foods and nutrients you personally need.

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Page Last Updated: 03/25/2014
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