More than half of U.S. adults are overweight or obese, and more than one-third of U.S. adults are trying to lose weight. Increasingly, they are turning to weight loss supplements for help. The most widely used weight loss supplement is ephedra, or ma huang. The active ingredients in ephedra-ephedrine alkaloids—are compounds with potentially powerful stimulant effects on the nervous and cardiovascular systems. The dietary supplement industry estimates that as many as 3 billion servings of ephedra are sold each year in the United States and approximately 12 million individuals were using ephedra in 1999.

FDA regulates dietary supplements under DSHEA, which covers vitamins, minerals, herbs or other botanicals, amino acids, certain dietary substances, or derivatives of these items. A product that contains any active ingredient not on the preceding list—such as synthetic ingredients that are sold in over-the-counter drugs and prescription medications—may not be marketed as a dietary supplement. DSHEA requires that dietary supplement labels include complete lists of ingredients and the amount of each ingredient in the product. Products may be labeled as “proprietary blends” and must list all ingredients but do not need to list the amount of each ingredient. In addition, dietary supplements cannot be promoted as a treatment, prevention, or cure for a specific disease or condition. To the extent that therapeutic claims are made, FDA may take action.