Sunscreen doesn’t just prevent sunburns and skin cancer; using it daily can slow down your skin’s aging too, says a study published in the Annals of Internal Medicine.

Australian researchers found that when adults regularly used broad-spectrum sunscreen, they were less likely to show increased wrinkling over a four-and-a-half-year period compared to adults who used sunscreen every once and a while, reports Barbara Mantel of NBC News.

This is the first study showing that sunscreen prevents skin aging, and the results show year-round use of sunscreen significantly slows the aging of skin caused by the sun’s ultraviolet rays, Dr. Adele Green of Royal Brisbane Hospital in Queensland told the Gupta Guide.

“Previous research has shown that skin aging is associated with an increased risk of actinic keratoses and melanoma, and now we have the first randomized trial to show that sunscreen retards skin aging,” Green said.

The sunscreen used in the study had a SPF of 15, which blocks about 94 percent of ultraviolet B rays. Stronger preparations have only a small additional effect; one with an SPF of 40 filters about 97.5 percent, Green told Mantel.

“The more important issue is applying the sunscreen well and reapplying it often,” and you should make sure that sunscreen is broad spectrum, he said. The study also found that daily beta-carotene supplementation had no effect on skin aging.

The study shows that just 15 minutes of sun on any part of your body can age the skin, and it is never too late to start using sunscreen, said Dr. Nancy Snyderman of NBC News. Even in middle age, if you start using sunscreen, you can role back the aging of your skin, she said. Here’s NBC’s video clip: