Dermatologists have warned for years that indoor tanning can cause skin cancer and should be avoided. The doctors' latest broadside comes in a selective review of scientific evidence on the risks and benefits of indoor tanning. Researcher Jody A. Levine, M.D., is a pediatrician and senior dermatology resident at SUNY Downstate Medical Center in Brooklyn, N.Y.

"We know that ultraviolet radiation is a carcinogen just like tobacco," Levine tells WebMD. "Radiation use has been declared a carcinogen by the National Institutes of Health. And the World Health Organization recognizes that no person under 18 should use a sun bed."

Levine and colleagues conclude that indoor tanning is a dangerous practice — especially for teens. The American Academy of Dermatology and the American Medical Association have called for a ban on the sale and use of tanning equipment for nonmedical purposes. And the FDA and CDC each encourage people to avoid the use of tanning beds and sun lamps.