Weight loss drugs and supplements often contain chemicals, such as ephedra and bitter orange, called sympathomemetic amines that work like adrenaline to increase metabolism and "turn on" the nervous system. Ephedra was a highly popular weight loss supplement before the
Food and Drug Administration banned over-the-counter sales in 2004.
A federal judge recently overturned the ban at least temporarily, but most supplement companies are unlikely to include ephedra in their weight loss products because of fear of lawsuits. The FDA claims to have registered nearly 1,000 cases of ephedra toxicity, some of which were linked to stroke and heart attack. Supplement company scientists countered that the FDA's evidence was scientifically unsound. Weight loss supplement companies substituted other stimulants, such as bitter orange, so they could continue to sell an effective product.
Critics of the industry charged that bitter orange was also dangerous and should be banned. Researchers from the University of Connecticut School of Pharmacy found that a single dose of bitter orange (22 milligrams) had no effect on the electrocardiogram or blood pressure.