Your Burning Sunscreen Q's Answered!

Julie Schott, SELF magazine

Ok, ok, I've been talking a lot about sun protection recently. But it's brought on a whole slew of new sunscreen questions! I asked Dr. Jennifer MacGregor of Union Square Laser Dermatology in New York City to answer three crucial ones. Read her enlightening answers and you'll be that much closer to a perfectly skin-safe summer!

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How do I know if my sunscreen is expired?
Some sunscreens have an expiration date printed on the bottle (it's usually microscopic, so scan the bottle closely!). Some don't. And--to make things more complicated--different formulas last longer than others. Chemical sunscreens become less active over time, while physical blockers (like zinc and titanium) stay stable for up to three years, says Dr. MacGregor. If you can't find the expiration date, stay on the safe side: "Toss the sunscreen after one year," advises Dr. MacGregor.

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I've heard spray sunscreens don't work as well as lotions or creams. True? Spray sunscreens work just as well as the others, but only if you apply enough of it, says Dr. MacGregor. That can be hard to do with a fine mist on a windy day. To guarantee you're getting adequate coverage, make sure you have a visible layer of the product all over your skin (even if it's clear, you can still see a wet film), and then rub it in evenly.

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How can I reapply sunscreen while I'm already wearing makeup?
For adequate sun protection, sunscreen should be reapplied every two hours--an annoying task when you don't want to mess up your makeup. The fix: Layer on a tinted SPF. "It's really easy since the sunscreen is also in the makeup," she adds. "You get protection and even skin."

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