Reduce wrinkles

• Retinoids. Both prescription (stronger) and OTC versions are proven to improve wrinkles: "They really work," says L.A./New York dermatologist Karyn Grossman. "They smooth skin by increasing cell turnover and collagen production." The key is to stick with the program: It takes at least six weeks to see the effects on your skin.
• Peptides also smooth skin and spur collagen growth—and they can be used in conjunction with retinol for more powerful results, says New York dermatologist Patricia Wexler: "They're great together, used at night."
• Antioxidants help protect skin from free radicals during the day. "Many sunscreens are already packed with them—or you can layer them underneath," says Grossman. Antioxidants also repair skin as you sleep, though some—like vitamin C—can be irritating if used at the same time as retinol.
• Sunscreen. The sun is the quickest ager there is. "At the bare minimum, you need SPF in the morning under makeup," Grossman says. "Ideally, you should reapply every two hours—you can use sunscreen or high-SPF foundation."
• Sleep on your back (you're essentially ironing in wrinkles by crushing your face into a pillow), and don't smoke (it induces major wrinkling and deprives your skin of oxygen).