woman examining skin

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Know the Facts First

It might surprise you to know that levels of collagen—the protein that keeps skin firm—start to dwindle as early as your teens, says New York City dermatologist Patricia Wexler, MD. Yet most women start to notice fine lines and slackness of skin around age 25. "Genetics has a lot to do with the way we age," Wexler says, "but certainly how we take care of the skin plays a predominant role in how we can change that."