Article image

by Dr Jane Moore

June 1, 2004

Buyer beware

Don’t assume that the ingredients listed on the supplement label, and only those ingredients, are present in the amounts stated. There is essentially no regulation of the supplement industry.

Be aware that supplements sometimes include anabolic steroids, ephedrine, caffeine, and other substances that may not be listed on the label and may produce a positive test for banned substances. More importantly, they may damage your health.

Herbs can be especially dangerous when taken with certain prescription drugs or over-the-counter medications. You should tell your physician about any herbal supplements you are taking.

Don’t expect herbal supplements to take the place of hard training as a means of improving your performance.


Banish joint pain. Lose weight. Improve your vision. Have more energy. Perform better. Prevent heart disease. Stop hot flashes. Sleep better. Improve your memory. Build muscle. Improve your nutrition. Enhance athletic performance. Improve strength. Improve endurance. Make stronger bones. Improve your concentration.
Supplements are everywhere. You can find them on drugstore shelves, in advertisements on television, in magazines and newspapers, and on the Web. They promise to relieve pain and inflammation, provide energy, improve performance, keep you healthy, improve sleep, improve memory, and more.

Do they really work? Claims need to be carefully evaluated. How do they work? Are they supported by solid scientific evidence? Is there proof of safety or effectiveness? Will they interact with other supplements or with prescription medications? What’s the proper dose? Are they legal? What are the potential adverse effects?
There are many different types of supplements. The Dietary Supplement Health and Education Act of 1994 (DSHEA) defines dietary supplements as products “intended to supplement the diet.” A supplement may include one or more vitamins, minerals, herbs or botanical products, amino acids, dietary substances, concentrates, metabolites, extracts, or combinations of any of those ingredients.

Who uses supplements?

From 1994 to 2001, sales of dietary supplements grew from $8.8 billion to almost $18 billion per year. Almost half of the U.S. population uses some type of dietary supplement regularly. Use of supplements has always been higher in athletes than in the general population.
A survey taken during the 2000 Summer Olympics reported use of supplements by 91% of the 592 American athletes at the Games. The substances athletes reported using included vitamins, minerals, proteins, amino acids, herbs, creatine, energy bars, and energy drinks. The most commonly used supplement was a multivitamin with minerals as reported by 83% of the male athletes and 87% of the female athletes.

Reasons for taking supplements

Many people assume that herbal supplements are safe and without the side effects on medications because they are “natural” and are available for purchase without a prescription. This misconception can be dangerous because herbs, like medications, can have adverse effects. The risk of adverse effects increases when herbs and other supplements are combined with over-the-counter and prescription medications.

Athletes use supplements to enhance performance by boosting energy levels, increasing muscle mass, or reducing body fat. Many performance-enhancing substances are banned from high-level sports to protect the health and safety of athletes and to ensure that no athlete has an artificially induced advantage over the competition. Athletes must know which substances are banned and be aware that dietary supplements may contain prohibited substances.

Regulation of dietary supplements

Dietary supplements belong to a category falling between “food” and “drugs” and so are outside of the regulatory jurisdiction of the United States Food and Drug Administration (FDA). Unless a supplement specifically claims to diagnose, mitigate, treat, cure, or prevent a specific disease, it is not subject to regulation. Such claims are limited to drugs and must be supported by proof of safety and efficacy. However, there are many Web sites pertaining to health-related uses of supplements.

While most supplements are safe, there have been problems with contamination and with inaccurate listing of ingredients on labels. Containers may include much more or much less of the listed amounts of ingredients. They may also contain added substances not listed on the label. Some of these substances can cause failed doping tests for athletes. The FDA must prove that a product is unsafe for it to be removed from the market.

Manufacturers are not required to report adverse events related to supplement use. Even generally safe supplements such as vitamins and minerals can be toxic if taken in huge doses.

There is really no foolproof way to determine if a product is safe. Vitamin and mineral supplements labeled USP (United States Pharmacopoeia) have passed tests for dissolutions, disintegration, potency, and purity. Nationally known food and drug manufacturers generally make supplements under the strict quality control procedures they use for other products.

Resources information from the U.S. Food and Drug Administration Center for Food Safety & Applied Nutrition information on current studies of various supplements independent test results and information on supplements and manufacturers free database with scientific data on herb use Herb Research Foundation, searchable database Site for the American Botanical Council subscription ($59/year) evidence-based clinical information on natural medicines independent test results and information on supplements

Chamberlain, L.V. What the Labels Won’t Tell You: A Consumer Guide to Herbal Supplements. Interweave Press. 1998.

Foster, S. and V.E. Tyler. Tyler’s Honest Herbal. A Sensible Guide to the Use of Herbs and Related Remedies (4th ed.). The Haworth Herbal Press Inc. 1999.

Hathcock, J.N. Vitamin and Mineral Safety. Council for Responsible Nutrition. 1997.

This month's fitness article about dietary supplements was written by Jane Moore, M.D., who is a member of the USMS Fitness Committee and the USMS Sports Medicine Committee. Jane is also the 2002 co-recipient of the Ransom Arthur Award, along with her husband, Hugh.


  • Health and Nutrition


  • Nutrition
  • Fitness
  • Sports Medicine