First developed in 1928, sunscreen continues to evolve as research yields new insight into the best ways to protect the skin from the damage that ultraviolet (UV) radiation can cause. Sunscreen manufacturers have developed ways to make the formulations more effective and longer-lasting and researchers are investigating alternative ways to provide protection through dietary supplements.
Speaking today at ACADEMY ‘06, the American Academy of Dermatology’s (Academy) summer scientific meeting, dermatologist Henry W. Lim, M.D., F.A.A.D., chairman and Clarence S. Livingood chair of the department of dermatology at Henry Ford Hospital in Detroit, Mich., discussed the latest in sunscreen protection.
“Initially, sunscreen was developed to protect against the short-term harmful effects of UV exposure such as sunburn,” said Dr. Lim. “Today, we know that sunscreen does much more than protect us from sunburn. It also can protect against long-term effects like aging and skin cancer, aiding the body’s natural defense mechanisms against UV radiation by absorbing, reflecting or scattering the sun’s rays on the skin.”
UV radiation is broken into three types of wavelengths: UVA, UVB and UVC. UVA has the longest wavelength, is not absorbed by the ozone layer and it penetrates the skin deeper than UVB. UVB is partially blocked by the ozone layer and causes sunburns. Because UVC is totally absorbed by the earth’s atmosphere, we receive it only from artificial radiation sources.
New technology has allowed manufacturers to combine and stabilize the ingredients that block both UVA and UVB in special formulations.
“Existing sunscreens that contain Parsol 1789, or avobenzone, do a good job of blocking UVB, but their protection against UVA starts to weaken after a few hours of sun exposure. The new formulations combine avobenzone and oxybenzone, are much more stable and retain their ability to protect against UVA for a longer period of time,” Dr. Lim said.
Researchers also are investigating how certain anti-oxidants like vitamin E, beta carotene and vitamin C can protect the skin. In addition, the UV-protective properties of green tea and fish oil are being investigated.
“While research to confirm the UV-protective benefits of anti-oxidants continues, one advantage of this type of sun protection would be that a person could protect their entire skin surface with an oral treatment and not have to worry about it washing, sweating or rubbing off like sunscreen can.
“The most important thing to know about any type of sunscreen is that regardless of skin type and ethnicity, everyone needs to use it,” advised Dr. Lim. “For basic protection year-round, the American Academy of Dermatology recommends using a broad-spectrum sunscreen - one that protects from both ultraviolet A (UVA) and ultraviolet B (UVB) rays - with a sun protection factor (SPF) of at least 15. Whether you choose a cream, lotion, gel or wax stick, you should select a sunscreen you’re comfortable with so that you will use it regularly.”
The Academy recommends that everyone be Be Sun SmartSM by wearing sunscreen and:
- Wearing protective clothing, such as a long-sleeved shirt, pants, a wide-brimmed hat and sunglasses, where possible.
- Seeking shade when appropriate, remembering that the sun’s rays are strongest between 10 a.m. and 4 p.m.
- Using extra caution near water, snow and sand as they reflect the damaging rays of the sun which can increase your chance of sunburn.
- Protecting children from sun exposure by applying sunscreen.
- Getting vitamin D safely through a healthy diet that includes vitamin supplements. Don’t seek the sun.
- Avoiding tanning beds. Ultraviolet light from the sun and tanning beds causes skin cancer and wrinkling. If you want to look like you’ve been in the sun, consider using a sunless self-tanning product, but continue to use sunscreen with it.
- Check your birthday suit on your birthday. If you notice anything changing, growing, or bleeding on your skin, see a dermatologist. Skin cancer is very treatable when caught early.
American Academy of Dermatology
Revision date: July 6, 2011
Last revised: by Jorge P. Ribeiro, MD