Although changes in diet, exercise, and sleep protect your skin from the inside, it's essential to guard it from external elements as well. Wearing sunscreen year-round is key—and diligence is important. With too much sun exposure, blood vessels in the skin grow and the stimulation from UV light causes enzymes in collagen and elastin to break down. Sunburns set up an inflammatory response that breaks down proteins in the skin, accelerating the loss of collagen and elastin, which can cause the skin to wrinkle. Look for a sunscreen that contains an SPF of 30 or higher.