Buyer Beware

Death by Diet Medications recently found in 69 diet supplements could cause heart attacks or worse Steve Cross

The YouTube promo for Zhen de Shou weight-loss capsules is farcical: The camera slowly pans across photos of depressed overweight girls becoming euphorically thin and warns, "Beware of cheap imitations." But the ad hides a real danger. According to recent tests by the Food and Drug Administration, Zhen de Shou and 68 other weight-loss supplements manufactured in the U.S. and abroad contain undeclared pharmaceuticals. That means millions of Americans popping over-the-counter diet pills might also be unwittingly ingesting medication at potentially deadly doses.

Nearly all the supplements that tested positive contain the appetite suppressant sibutramine, the generic name for Meridia, one of two prescription drugs approved for long-term obesity treatment. Never mind that administering it without a prescription is illegal; sibutramine elevates blood pressure and heart rate and can cause stroke and heart attack. In some supplements, the FDA detected sibutramine levels of four times the highest doctors can safely prescribe.

Worse yet, says Pieter Cohen, a physician at Cambridge Health Alliance in Massachusetts, because the products don't list the drugs, "when they do cause problems, people might not make the connection." Cohen discovered this firsthand after some of his patients complained of heart palpitations. It turned out they had been taking Brazilian Diet Pills, which tested positive for a drug that the body turns into amphetamine.

In its investigation, the FDA also found in diet pills such drugs as rimonabant, an appetite suppressant that was pulled from European shelves and never approved in the U.S. because of a potential link to suicide, and phenolphthalein, a laxative linked to cancer and discontinued in 1999. Despite the FDA's warning to consumers last December, as of press time, manufacturers had recalled only three of the supplements. The agency is following up on all the products, says Mike Levy, who oversees new drugs and labeling compliance at the FDA, and can seize the goods if companies don't voluntarily pull them.