Seek out information, such as American Herbal Products Association handbooks that discuss scientific studies of certain supplements and potential side effects. Scientific studies appear on Medline, a database run by the National Library of Medicine available free through the Internet. But don't believe commercial endorsements on the Internet, experts advise. The Food and Drug Administration has 900 reports of side effects, including heart palpitations and psychosis, heart attacks and strokes. Several states have banned ephedrine-containing supplements.
Federal limitations are pending.
FDA has recorded two deaths and 10 cases of hepatitis or other liver abnormalities in users. Banned in Canada and severely restricted in Germany, comfrey root originated as a poultice to reduce swelling but later was used internally. FDA knows of one death. A hormone that turns into estrogen and testosterone inside the body. The National Institutes of Health says there is no evidence that DHEA fights aging as it claims, and warns that it could increase cancer risk and may lead to liver damage even when taken briefly.