We all knew it intuitively, but now we have data that sunscreen does more than simply protect your skin from cancer and sunburns. A new study shows that sunscreen can protect against wrinkling, spotting, and loss of elasticity caused by exposure to ultraviolet radiation. Australian researchers followed 900 patients for 4 years. Some were told to use sunscreen daily, and instructed in its proper use (including re-applying after being outside for a few hours, after going in water, or profuse sweating). Other participants were given no instructions regarding the use of sunscreen. The investigators then used a technique called micro topography: They made sensitive silicone impressions on the back of each participant’s hand. Skin surface patterns reflect the severity of damage to deeper skin layers, including the collagen and elastic fibers. So, if you spend time outside during the day, you should use sunscreen. And remember, SPF is not a marker for how long you can stay out in the sun. An SPF 15 sunscreen blocks about 93% of UV-B rays, while SPF 30 blocks 97%. You want a sunscreen that protects against both UV-A and UV-B, and has an SPF of 50 or below. The Envoironmental Working Group prefers sunscreens free of oxybenzone and retinal palmitate (a form of vitamin A). I’m Dr. Michael Hunter The fine print: The material contained herein is for general use, and may not apply to you as an individual. As such, it is not intended to be medical advice for an individual, and you should check with a valued health provider with any questions or concerns.