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.
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 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:
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."
In addition to these claims, there are some additional claims to be aware of that you might see on a label.
While there are several organizations that offer testing of dietary supplements, the testing methods and standards used vary. NSF/ANSI 173 – Dietary Supplements was developed several years ago to provide a uniform standard for testing dietary supplements.
Under this 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 there are no unsafe levels of contaminants in the product such as heavy metals, pesticides and herbicides. Certification also helps make sure there are no unlisted ingredients, which is useful for those with allergies.