How do you know if a particular dietary supplement is safe and effective?

Credit: CC0 Public Domain.

Scientific evidence supporting the benefits of some dietary supplements (e.g., vitamins and minerals) is well established for certain health conditions, but others need further study.

Research studies on people to prove that a dietary supplement is safe are not required before the supplement is marketed, unlike for drugs.

This is due to the way dietary supplements are regulated by the U.S. Food and Drug Administration (FDA).

It is the responsibility of dietary supplement manufacturers/distributors to ensure that their products are safe and that their label claims are truthful and not misleading.

If the FDA finds a supplement to be unsafe once it is on the market, only then can it take action against the manufacturer and/or distributor, such as by issuing a warning or requiring the product to be removed from the marketplace.

The manufacturer does not have to prove that the supplement is effective, unlike for drugs.

The manufacturer can say that the product addresses a nutrient deficiency, supports health, or reduces the risk of developing a health problem, if that is true.

If the manufacturer does make a claim, it must be followed by the statement “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”

Dietary supplements are not intended to treat, diagnose, mitigate, prevent, or cure disease.

In some cases, dietary supplements may have unwanted effects, especially if taken before surgery or with other dietary supplements or medicines, or if you have certain health conditions.

Supplements should not replace prescribed medications or the variety of foods important to a healthful diet.

Do not self-diagnose any health condition. Work with your healthcare provider to determine how best to achieve optimal health.

Also, check with your healthcare provider before taking a supplement, especially if you take any medicines or other dietary supplements or if you have any health conditions.

In addition to talking with your healthcare provider about dietary supplements, you can search on-line for information about a particular supplement. It is important to ensure that you obtain information from reliable sources such as:

  • ODS dietary supplement fact sheets
  • Nutrient Recommendations: Dietary Reference Intakes (DRI) and Recommended Dietary Allowances (RDA)
  • Dietary supplement warnings and safety information from the U.S. Food and Drug Administration
  • Consumer information from the Federal Trade Commission

If you care about supplements, please read studies that vitamin C could help treat heart rhythm problem, and new supplements can boost strength and cognition in older people.

For more information about supplements, please see recent studies about vitamin that is critical for cancer prevention, and results showing this vitamin may help fight COVID-19, reduce inflammation.