Guide to Understanding Dietary Supplement Claims

Dietary supplements have become very popular in recent years as consumers have become more interested in leading healthier lives. With so many choices, it can be difficult to figure out the best supplement to purchase. 

In the U.S., products sold as dietary supplements are not permitted to claim that they can treat, prevent or cure a specific disease or condition. However, they can make other claims on the product label:

Health Claims

Disease or health claims show a link between a food or substance and a disease or health-related condition. An example of this type of claim would be, "calcium and a lower risk of osteoporosis" if a supplement contains sufficient amounts of calcium.

Structure/Function Claims

Structure/function claims refer to the supplement's effect on the body's structure or function, including its overall effect on a person's well-being. Examples of structure/function claims include:

  • "Calcium builds strong bones."
  • "Antioxidants maintain cell integrity."

Nutrient Content Claims

Nutrient content claims describe the level of a nutrient in a food or dietary supplement. For example, a supplement containing at least 200 milligrams of calcium per serving could carry the claim "high in calcium." A supplement with at least 12 mg per serving of vitamin C could state on its label, "excellent source of vitamin C."

Other Types of Claims

Additional claims to be aware of include:

  • Outrageous Claims. Most of us have seen supplements that promise to help make us thinner, smarter, stronger or faster or improve our sex life without making any other changes in lifestyle. Just as with other products, if it sounds too good to be true, it probably is.
  • “All Natural.”  Unlike the term “organic,” “all natural” is not an official term that is regulated by the federal government and does not offer any guarantee as to the product’s safety.
  • “Pharmaceutical Strength.” This is another one to watch out for, as there is no such thing as pharmaceutical strength for over-the-counter supplements.

Product Certification

While there are several organizations that test dietary supplements, testing methods and standards vary. NSF/ANSI 173: Dietary Supplements was developed several years ago to provide a uniform standard for testing dietary supplements. Under this American National Standard, products are tested to confirm that what’s on the label is actually present in the product. In addition, testing is conducted to confirm that the product contains no unsafe levels of contaminants such as heavy metals, pesticides and herbicides.

Some product labels may reference GMP or good manufacturing practices registration. While important, GMP registration only applies to the production facility and does not guarantee that the contents of the product match what is shown on the label or that the product is free of banned substances.

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