With so many sunscreen options on the market, it can be confusing to know which ones offer the best protection. A new study further emphasizes the importance of selecting a broad-spectrum sunscreen to protect the skin against skin cancer and early aging. "Broad spectrum" means that a sunscreen provides protection against ultraviolet A (UVA) and ultraviolet B (UVB) rays.
At the American Academy of Dermatology's Summer Academy Meeting 2011 in New York, dermatologist Steven Q. Wang, MD, Director of Dermatologic Surgery and Dermatology at Memorial Sloan-Kettering Cancer Center in Basking Ridge, N.J., presented results from a study on sunscreens and antioxidants. The study, published in the Journal of the American Academy of Dermatology, found that in addition to protecting the skin from UV exposure that causes skin cancer, current broad-spectrum sunscreen products offer protection from free radicals—molecules that cause skin damage and aging— and the majority of the protection is from UV filters rather than antioxidants.
Environmental exposure such as UV radiation, pollution, and smoking all can contribute to the development of free radicals in the body, which can cause skin damage and aging.
In young, healthy skin, the body uses a sophisticated defense system to absorb free radicals; whereas, in older individuals this defense system can be depleted. When the body's own defense isn't working as it should, free radicals build up from UV exposure and other environmental sources, and can lead to skin damage and wrinkles.
"Our research found that a product with high UVA protection blocks or absorbs more harmful radiation from the UVA spectrum and reduces the total amount of free radicals generated in the skin," said Dr. Wang. "Exposure to UVA rays and UVB rays can lead to the development of skin cancer. This is why choosing a broad-spectrum sunscreen that protects the skin from both types of rays is so important."
Dr. Wang added that the U.S. Food and Drug Administration's (FDA) new sunscreen rules will make it easier for consumers to make informed decisions about choosing sunscreens with UVA and UVB protection. By June 2012, manufacturers are required to follow specific testing and labeling rules for making a broad-spectrum claim in a sunscreen and indicating which sunscreen products can reduce the risk of skin cancer and early aging.
Dr. Wang explained that sunscreens that filter UV rays are providing "passive" protection by absorbing or reflecting harmful UV rays from the skin. By adding antioxidants to sunscreens, Dr. Wang believes that these combination sunscreens could offer a second, "active" level of protection. While not necessary for UV protection, the antioxidants could boost the body's natural antioxidant reserve and stop any free radicals generated from UV that pass through the filters.
"Adding antioxidants to sunscreen is an innovative approach that could represent the next generation of sunscreens, which would not only filter UV radiation, but also offer other tangible skin health benefits," said Dr. Wang. "Theoretically, supplementing sunscreens with antioxidants could boost the body's natural defense against the formation of UVA-induced free radicals; therefore serving as a second layer of protection against UV radiation that passes through the first layer of UV protection."
Due to the unstable nature of antioxidants when added to sunscreens and that there is no single test to sufficiently measure their concentrations, Dr. Wang stressed that it was a challenging task to determine the final concentration of antioxidants in each product and differentiate their free radical protection.
"This is an exciting area of research in sunscreens. However, we believe further study is needed to gauge the benefits of incorporating antioxidants in sunscreens," explained Dr. Wang.
In the meantime, Dr. Wang stressed the importance of applying broad-spectrum sunscreen with SPF 30 or higher to help stop skin cancer and prevent skin damage and early aging. In addition, people need to limit UV exposure by seeking shade, wearing protective clothing, hats and sunglasses, and avoiding tanning beds.
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