"Waterproof" and "sweatproof" are no longer acceptable claims (because, it turns out, they're false). A "water resistant" claim must specify how long the sunscreen can stand up to swimming or sweating (either 40 or 80 minutes, based on testing).
"Broad spectrum"—a previously unregulated claim—now means that a sunscreen has undergone testing to ensure that it provides protection against both skin-burning, cancer-causing UVB rays (those included in the SPF rating) and skin-aging, cancer-causing UVA rays.
Only sunscreens with an SPF of 15 or higher that have passed the broad-spectrum test can claim to reduce the risk of skin cancer and premature aging anywhere on their packaging. If a sunscreen has an SPF below 15, or has not passed the broad-spectrum test, it can claim only to help prevent sunburn.
Tip: Don't try to mask the scent of self-tanner with perfume. If you've ever spritzed yourself with your favorite fragrance soon after applying a self-tanner, you probably learned the hard way that the combination can temporarily give your skin an eerie and otherworldly green tint. The likely reason? Some antioxidants used in fragrances chemically react with DHA—the ingredient in sunless-tan products that darkens your skin—causing patches of your tan to turn a light shade of green, says Ni'Kita Wilson, a cosmetic chemist and vice president of Englewood Lab in Englewood, New Jersey. To avoid a sci-fi pallor, resist the urge to apply fragrance (and other body products like deodorant and lotion) for at least six hours after self-tanning.
Pictured: La Roche-Posay Anthelios 50 Tinted Mineral Ultra Light Sunscreen Fluid, $33; laroche-posay.us.
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