"If you stay in the shade or use a sunscreen, you will see reversal of many of the changes in your skin," [Albert Kligman] says. "It won't become young skin again. The major changes -- wrinkles, bags, sags -- are going to stay. But the connective tissue underneath the top layer of the skin, the dermis, will definitely improve. The fibroblasts have a chance to make new collagen. Precancerous lesions simply disappear. After about two or three years of not being in the sun, you'll have what looks like a light peel, where a few upper layers of the skin have been removed, leaving the skin smoother looking."