It should come as a surprise to absolutely no one that summer can do a serious number to our skin — both face and body included. Blame it (mostly) on the sun. “UV rays can impair the skin barrier by causing significant inflammation and producing free radicals that can damage the skin,” says David Kim, M.D., a board-certified dermatologist in New York City. “This can lead to collagen degradation, reduced wound healing, and DNA damage that can lead to skin cancer.”