At least 170,000 cases of skin cancer each year are linked to indoor tanning, according to an analysis published online Tuesday in the British medical journal BMJ.
Those cancers include basal-cell carcinomas and squamous-cell carcinomas, two common types of non-melanoma skin cancers that aren't usually life-threatening, the study says. People who have ever used indoor tanning are 29 percent more likely to develop basal-cell carcinomas than those who have never used them.
Indoor tanners are 67 percent more likely to develop the more serious squamous-cell carcinomas compared with those who have never tanned indoors, says the study's senior author Eleni Linos, an assistant professor of dermatology at the University of California-San Francisco.
That suggests indoor tanning is responsible for about 5 percent of non-melanoma skin cancers, the most commonly diagnosed cancers in the USA, says Thomas Glynn of the American Cancer Society. Non-melanoma skin cancers strike about one in five Americans during their lifetime, including 30 percent of whites, Linos says. Those who started tanning indoors before age 25 had the highest skin cancer risk, according to the analysis, which included 12 studies involving 80,000 people in six countries.
Other research has linked indoor tanning to malignant melanoma, the deadliest type of skin cancer, Linos says. The International Agency for Research on Cancer has classified ultraviolet radiation from tanning beds as a Class 1 carcinogen, the same category as tobacco smoke and asbestos. Linos says the study lends support to state and city efforts to ban kids and teens from tanning salons.
John Overstreet of the Indoor Tanning Association says consumers should be free to make informed choices about the benefits and risks of indoor tanning. "UV exposure, whether from the sun or a sunbed, has many benefits." He cites research suggesting ultraviolet radiation from tanning beds provides vitamin D.
Scientists are studying the role of vitamin D in preventing health problems, but the studies use vitamin D supplements, not UV exposure.
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Read the original article on USA Today. Copyright 2012.