Frequently Asked Questions

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What are dietary supplements?

Dietary supplements include any products taken by mouth that contain a "dietary ingredient" intended to supplement the diet. This would include vitamins, minerals, herbs, botanicals, amino acids and concentrates, metabolites, constituents, and extracts of these substances. Dietary supplements are not classified or considered to be drugs.

Who ensures the safety of dietary supplements in the U.S.?

By law, manufacturers are responsible for ensuring their supplements are safe before they are marketed. Unlike drug products, dietary supplements are not reviewed by the government before being made available to the consumer.

Are there any independent standards for dietary supplements?

Yes. NSF/ANSI Standard 173 – Dietary Supplements was developed several years ago to provide a uniform standard for testing these products to help confirm what's on the label matches what's in the bottle. The NSF Certification is based on this standard and includes product testing along with facility audits to confirm that the manufacturer is observing good manufacturing practices (GMPS) that have been established for their industry.

What information needs to be on the label?

The U.S. Food and Drug Administration (FDA) requires dietary supplement product labels to contain the following information:

Are expiration dates required?

The FDA does not mandate that supplement manufacturers include an expiration date on their products. Manufacturers that have data to support that date claim often put an expiration date on the label.

Don't purchase supplements with expiration dates close to the date of purchase, and if you have any supplements at home that are past the expiration date, throw them out. These products can lose potency over time.

Is it necessary to check with a health care professional before using supplements?

Dietary supplements may not be totally risk free under all circumstances. Some supplements can interact with over-the-counter or prescription medications or have unwanted effects during surgery, while others may contain active ingredients that can cause adverse reactions in some users. People who want to use supplements are encouraged to contact their health care provider prior to taking a dietary supplement.

For additional information about supplements, visit the NSF Dietary Supplement Web page or contact the NSF Consumer Affairs Office at info@nsf.org.


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