More than half of Americans use dietary supplements, and use has been increasing each year, with annual sales reaching $28 billion in 2010—despite mounting evidence that for most well-nourished adults, supplementation has no clear benefit and might even be harmful, according to research published in the Annals of Internal Medicine.
“Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements,” an editorial introducing the three studies, states unequivocally that “most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided.”
In light of these findings, pharmacists are well positioned to counsel patients on legitimate versus unnecessary use of dietary supplements. Explain that supplements are not intended to treat, cure, or alleviate the effects of diseases, nor can they completely prevent diseases. Legitimate uses include taking folic acid during pregnancy to reduce the risk of brain and spinal cord birth defects, or taking calcium and vitamin D supplements if natural sources do not supply the recommended daily amounts.
“There are no miracle cures, despite what the health gurus say,” said Anne Hume, PharmD, FCCP, BCPS, Professor of Pharmacy, and Complementary and Alternative Medicine Section Editor of APhA’s Handbook of Nonprescription Drugs. Encourage patients to “try to use diet and exercise [instead] of these products,” Hume said, and stress the following points:
The last point is especially important. Inform patients that unlike new drugs, dietary supplements are not FDA reviewed and approved for safety and effectiveness before they are marketed. FDA reviews supplements for safety only if they contain a new ingredient, and can take dietary supplements off the market if they are found to be unsafe or adulterated or if the product claims are false or misleading.
Explain that many supplements contain ingredients that have strong biological effects and may not be safe in all people. Taking a combination of supplements, using these products with medications, or substituting them in place of prescribed medications could lead to harmful, even life-threatening, results. Refer patients to FDA’s list of known tainted supplements and fact sheet on dietary supplements.
Inform patients that some supplements may cause adverse effects before, during, or after surgery. For example, bleeding is a potential adverse effect of garlic, ginkgo biloba, ginseng, and vitamin E. Kava and valerian act as sedatives and can increase the effects of anesthetics and other medications used during surgery.
Urge patients who experience adverse effects from supplements to contact their health care provider immediately. Both patients and their providers should report the problem to FDA.
Advise patients to look for the USP Verified Mark on product labels and packaging. The mark indicates that a dietary supplement has been voluntarily submitted to USP by its manufacturer and has successfully met the strict criteria of the USP Dietary Supplement Verification Program, including testing against federally recognized USP–National Formulary (NF) standards.
Herbs at a Glance, a downloadable fact sheet listing common names, what the science says, potential adverse effects and cautions, and resources for more information, is available from the National Center for Complementary and Alternative Medicine. The National Consumers League offers a brochure, “A Consumer Guide to Dietary Supplements.”