Even the fittest of us are not exempt. In 2003 U.S. Olympic marathon runner Deena Kastor was diagnosed with skin cancer. "As athletes, we consider ourselves healthy," Kastor says. "We have a strong heart, lungs and muscles. Our skin, however, is our largest organ, so we better take care of it."
The good news: This is one cancer you can actively prevent. "Skin cancer is completely curable when detected early," says Dr. Elizabeth K. Hale, clinical assistant professor of dermatology at the New York University School of Medicine.
Even if you're not in the blazing sun for months at a time, you still need daily protection from the sun's intense rays. We've sorted through all the complicated label claims and confusing acronyms (SPF, UPF, UVB) found on sunscreen these days to help you choose and apply the right sun protection. Use it every day--your skin will thank you.
UV ExplainedThe World Health Organization has named ultraviolet radiation (UV) a proven human carcinogen. "The sun not only contributes to the development of skin cancer but also aging of the skin (called photoaging), which manifests itself as undesirable sun spots, wrinkles, roughness or leathery appearance," Hale explains.
The UV spectrum comprises three forms of rays: UVA, UVB and UVC. The last is filtered out by the ozone layer and is inconsequential when it comes to skin damage. UVA categorizes the long wavelength rays that account for up to 95 percent of UV radiation. Present during all daylight hours, UVA rays can travel through glass and clouds and penetrate the deeper layers of the skin, accelerating the signs of aging.
UVB rays, 30 to 50 times less prevalent than UVA rays, are responsible for the common sunburn, and damage the superficial layers of the epidermis. The UVB peak times in the Northern Hemisphere are 10 a.m. to 4 p.m., April through October. Exposure to UVB rays is a known cause of skin cancer, but recent studies suggest that UVA rays may be just as damaging.
For adequate protection from both UVA and UVB, use a sunscreen that provides broad-spectrum or multi-spectrum protection, not just a high sun protection factor (SPF). A sunscreen's SPF rating only indicates how long you can stay in the sun without getting sunburn. For example, an SPF rating of 15 means you could stay in the sun 15 times longer with sunscreen on than without before getting burned. Keep in mind that SPF refers exclusively to UVB blockage.