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Scientist: Don't Trust Sunscreen
The latest skin-cancer prevention advice is to stop trusting sunscreen as the front line of defense against harmful rays.
Instead, wear sunblocking clothing or stay out of the sun altogether, experts say.
Sunscreen has been shown to protect against UV skin damage as well as basal carcinomas and squamous cell carcinoma—two of the three most common skin cancers. However, it has not been conclusively shown to protect against melanoma , the most fatal kind, said Stephan Lautenschlager of the Outpatient Clinic of Dermatology at Triemli Hospital in Switzerland.
Lautenschlager and his colleagues carried out a comprehensive review on sun protection strategies worldwide, recently detailed online in the journal Lancet.
"Wearing sun-protective clothing and a hat and reducing sun exposure to a minimum should be preferred to sunscreens," Lautenschlager said. People tend to sunbathe for social reasons, he said. "Nevertheless, sunscreens should not be abused in an attempt to increase time in the sun to a maximum."
No wet T-shirts
The best clothing for sun protection is tightly woven, thick garments made of denim, wool or polyester, not cotton, linen or acetate, he said. Dry material or clothes that have shrunk after washing are denser and better at blocking UV rays than wet, stretched or bleached clothing.
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Outdoors, wear sunscreen and lots of it. Zinc or titanium oxide sunscreens scatter UV light and yield fewer allergies, so they are better for children, he said. The more common sunscreen lotions, called organic sunscreens, absorb UV rays.
"The application of a liberal quantity of sunscreen is by far the most important factor for effectiveness of the sunscreen, followed by the uniformity of application and the specific absorption spectrum of the agent used," Lautenschlager said.
That is, don't treat the stuff like liquid gold. Smear it on. A shot glass-full should be applied 15 to 30 minutes before heading outdoors.
Look at your skin
While four out of five people are concerned about skin cancer, more than half have never been screened for skin cancer (54 percent) and nearly one quarter (23 percent) never examine their skin for changes to moles and blemishes, according to a recent survey by the American Academy of Dermatology.
More than 1 million new cases of skin cancer will be diagnosed this year, the AAD says, but when detected early, even melanoma is highly treatable.
To check yourself, regularly inspect all your skin, including the back, scalp, buttocks, soles of the feet, between the toes and the palms of the hands. Use mirrors when necessary.
Other tips from the AAD: Seek shade if you must be outdoors during the sun's strongest hours, between 10 a.m. and 4 p.m. Avoid tanning beds. Their UV light causes skin cancer and wrinkling. Use a self-tanning lotion if you want to look tanned.
- You and the Sun: 10 Burning Questions
- Risk Factors: Little Known Facts About Skin Cancer
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Robin Lloyd was a senior editor at Space.com and Live Science from 2007 to 2009. She holds a B.A. degree in sociology from Smith College and a Ph.D. and M.A. degree in sociology from the University of California at Santa Barbara. She is currently a freelance science writer based in New York City and a contributing editor at Scientific American, as well as an adjunct professor at New York University's Science, Health and Environmental Reporting Program.