The sun is the No. 1 culprit when it comes to aging. It’s easy to see what the sun has done to your skin over time. Compare the skin on the inside of your arm with that on the outside of your arm and on the back of your hands. If you’re like most people, the skin on the inside is smooth, clear, firm and unmarked, while the skin on the outside is “dry roasted”: freckled, dry, finely lined, not as firm, and possibly dotted with brown spots. And if you spend much time driving (in the U.S.), your left arm is probably worse than your right. Skin is simply closer to perfection “where the sun don’t shine.”
The most important thing you can do to keep your skin looking young, not to mention healthy, is never to expose unprotected skin to the sun. Slather your skin with a broad spectrum UVA/UVB sunscreen and apply it often. It’s the ultimate wrinkle cream.