Not Using Sunscreen
Credit: Getty Images

A recent study from the Annals of Internal Medicine found that over 4.5 years, people who used sunscreen daily showed 24 percent less skin aging than those who used it as they liked. "UV radiation causes the breakdown of both collagen and elastic tissue, causing wrinkling as well as [loss of] elasticity of the skin," says Rokhsar. If you think you're saving yourself by slathering on the aloe after forgetting your SPF, you're not. That is only cooling the burn, not battling the effects, says Rokhsar. So use sunscreen every day, whether you're on the beach or simply commuting to work.