Photo: Marko Metzinger/Studio D

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Don't Rely on the SPF in Your Foundation
"To measure SPF in a lab, the chemist puts 2 milligrams of the product on every square centimeter of skin," says Leslie Baumann, MD, professor of dermatology at the University of Miami. That's the equivalent of about half a teaspoon spread over your face! You probably don't wear that much foundation (if you do, please stop that too). Instead, apply a broad-spectrum SPF 30 sunscreen, wait a few minutes for it to soak in, and then follow with foundation. 

— Kate Sandoval