The Real Dirt On Antibacterial Soaps

Antibacterial soaps are no better than regular soap. Experts have said so for years. But that hasn't stopped millions of Americans from snapping up the supposedly superior germ killers--now 76 percent of the liquid-soap market. Part of the problem was the lack of rigorous studies to back up the experts' claims. But last week at the annual meeting of the Infectious Diseases Society of America, Elaine Larson, associate dean for research at Columbia University's School of Nursing, came up with the goods. In a randomized, double-blind, controlled study--the type of trial used to test pharmaceuticals--she surveyed 224 New York City homemakers. Half were given ordinary liquid soaps for a full year and the other half received antibacterial soaps. All participants' hands were cultured for germs at the beginning and the end of the study.

The results? At the outset, all participants' hands were teeming with 800,000 to 1 million bacteria. "That's normal," says Larson. "People can have up to 10 million on their hands." By the end of the year, tests revealed that they had just 300,000 or so. It didn't matter whether they used antibacterial soap or not. The difference was that they were taking more time to wash their hands thoroughly, particularly the fingers, which come in contact with the most foreign objects during the day.

Why don't antibacterial soaps do better? "The antimicrobial agent triclosan requires several minutes of contact to work," says Dr. Stuart Levy of Tufts University, author of "The Antibiotic Paradox." "Most people wash their hands for three to five seconds." Unfortunately, residues of antimicrobial soaps do linger on sinks and countertops, where Levy says they may contribute to the development of drug-resistant bacteria. A better solution for people with babies or immune-compromised patients at home is to use an alcohol-based gel, which kills germs by drying them out. Last week the CDC recommended these waterless germicides even in hospitals. Now, that's what the doctor ordered.