A popular belief is that you can safely tan when wearing the highest-number sunscreen at the beach. However, wearing sunblock doesn't guarantee protection from skin cancer if you're in the sun a lot. Being exposed to the sun for longer periods of time increases the risk of skin cancer, even while wearing sunblock. The American Cancer Society estimates there will be 62,000 cases of melanoma skin cancer and 7,900 deaths this year. There will also be more than 1 million cases of squamous and basal skin cancers, and about 2,800 deaths this year.
Sunscreens have been shown to filter out UVB rays, the ultraviolet (UV) rays that cause sunburn. However, sunscreens offer less protection against UVA rays that more deeply penetrate the skin and cause skin cancer. Even wearing a sunscreen with broad-spectrum UVA/UVB protection will only offer partial protection from the UV spectrum. As a result, lengthy exposure to the sun even while wearing sunblock will accumulate UV damage to the skin over time.
While a higher-number SPF (sunscreen protection factor) does offer more protection, it is only minimal. An SPF 15 sunscreen will block about 93 percent of UVB rays and an SPF 50 sunscreen will block about 98 percent. Experts recommend wearing a sunscreen including zinc oxide, titanium dioxide or avobenzone for protection against UVA. Reapply sunscreen often, at least every two hours and after swimming or sweating. For full coverage, apply at least two tablespoons of sunscreen. In addition to routinely applying sunscreen, use protective gear like hats or umbrellas. Stay out of the sun when the rays are strongest between 10 am and 4 pm. Minimize your sun exposure even when wearing sunscreen.
According to the Food and Drug Administration, manufacturers' claims such as "waterproof" and "sunblock" are unsubstantiated. The FDA will produce new regulations for sunscreen claims by 2007, recommending more accurate claims such as "water resistant" and "sunscreen". In the meantime, consumer lawsuits are pending against makers of the top sunscreens, alleging manufacturers are fraudulent in their label claims.
REFERENCES
1. Sunscreens faulted on cancer protection. The Associated Press, June 16, 2006:
http://www.usatoday.com/news/health/2006-06-16-sunscreen_x.htm
Posted by Elaine Gavalas on November 14, 2006 03:34 PM
