Using sunscreen every day can prevent skin from aging, according to a new study published today in the Annals of Internal Medicine.

While the use of sunscreen has long been thought to prevent aging, this is the first study to provide evidence of its effectiveness.  Australian researchers at the Queensland Institute of Medical Research followed 900 people, aged 55 and younger, for four years in a subtropical town north of Brisbane.  The study participants were randomly assigned to one of four groups:

• daily use of broad spectrum sunscreen and 30 mg of a beta-carotene supplement,
• daily use of sunscreen and a placebo,
• voluntary use of sunscreen and 30 mg of a beta-carotene supplement, and
• voluntary use of sunscreen and a placebo.

At the end of the four-year period, the skin of the participants in the daily sunscreen group had aged 24 percent less, compared to those who only used sunscreen at their own discretion, regardless of the age of the participants.

Beta-carotene supplements did not have any effect on aging skin.

When the study began in 1992, 58 percent of the participants had moderate photoaging.  In 1996, when the study was completed, that number had dropped to 48 percent, suggesting a reduction in skin aging for some participants. According to WebMD, photaging refers to changes in the skin from exposure to sunlight, including wrinkles, dryness, coarseness, freckles, “liver” spots, and a loss of elasticity, giving skin a leathery appearance.

Dr. Adele Green, one of the authors of the study, told The Gupta Guide that the research suggests “regular application of sun screen by middle-age adults will be associated with a cosmetic benefit and prevention of skin cancer.”  In other words, the use of sunscreen could prevent that dry leathery appearance.

Photoaging is mostly caused by UV-A radiation and is a not a natural part of growing older, according to Dr. Lawrence Gibson, a professor of dermatology at the Mayo Clinic. Dr. Gibson told CNN, in older patients, no photaging is evident on parts of their bodies which have not been exposed to the sun.

Dr. Gibson says the best way to prevent skin damage is to avoid the sun, especially in the middle of the day. When you are outside, The Skin Cancer Foundation suggests broad spectrum sunscreen, which protects against UVA and UVB rays, with an SPF of 15 or higher.  Reapply every two hours and don’t forget a hat and sunglasses.