Karina Giglio Jun 20, 2012
  Walk down the sunscreen aisle and you’ll encounter more code words than a CIA operative on a top secret mission. That makes it tough to choose the right formula. We asked top dermatologists to help us decipher the lingo so you can commit to a skin saver that’s right for you. What is a chemical sunscreen? Chemical sunscreens, such as those containing oxybenzone and avobenzone, work by absorbing the sun's rays. “The chemicals absorb the [ultraviolet] light so that it doesn’t penetrate the skin and cause damage,” explains Elizabeth Tanzi, dermatologist and codirector of the Washington Institute of Dermatologic Laser Surgery. These types of sunscreens should be applied 20 minutes before heading outside so they have a chance to sink into the skin. What is a physical sunscreen? Physical sunscreens, such as those containing zinc oxide and titanium, work by deflecting or blocking the sun's rays. “The light bounces off them, rather than being absorbed by the chemical,” Tanzi says. They start to work as soon as they’re applied, but are often accompanied by a telltale white or gray cast on the skin. Which type should you use? Physical sunscreens including Badger SPF 30+ Lightly Scented Certified Natural Sunscreen are a better option for sensitive skin because they don't contain chemicals that can cause irritation, redness or breakouts. They’re also great for oily or acne-prone skin, since they tend to be a bit drying. Chemical sunscreens including Coppertone Sport Lotion SPF 30 Sunscreen are better for dry or aging skin since they impart more moisture. How often should I reapply? You should reapply sunscreen every two hours, even if the product's label says it’s water-resistant or can last longer than that. “The moisture on your skin from sweating and oils will cause it to evaporate within two hours, even if you’re not swimming,” says Robert J. Friedman, dermatologic oncologist and clinical professor of dermatology at the NYU School of Medicine. The amount you reapply should be equal to a shot glass. What does "broad-spectrum" mean? Broad-spectrum sunscreens protect against UVA and UVB rays, both of which are harmful and can lead to skin cancer. UVA rays cause wrinkles and age spots, and can even pass through a window glass. UVB rays cause burning, but are blocked by window glass. What does "SPF" mean? SPF stands for Sun Protection Factor. It can help you determine the time it would take for your skin to burn when wearing the product and exposed to UVB rays. It is based on an equation; for example, if you can stay out in the sun 10 minutes before burning without a sunscreen, using a sunscreen with an SPF of 30 would allow you to resist the burn for 30 times longer or 300 minutes. Do I really need an SPF 30 or higher? SPF 30 provides plenty of protection, so you really don’t need to go higher. “With SPF 30, you’re getting 97 percent protection,” explains Kathy Fields, dermatologist and cofounder of Rodan + Fields and Proactiv. "Going higher isn’t worth it since you get less than a 1 percent improvement, but usually end up with a thicker formula." Can I use last year’s sunscreen? If you still have some lying around, throw it out. Sunscreens have expiration dates. Plus, they’re often left in hot places, which can compromise the effectiveness of the ingredients. Is there anything else you always wanted to know about sunscreen but were afraid to ask?

Photo: Design Pics/Thinkstock




About the Author:Karina Giglio is a lifestyle, beauty and health writer whose work has appeared in numerous national publications including Women’s Health, Washingtonian, Ladies Home Journal, OK!, Allure, Fitness, Marie Claire, Bride’s and The New York Post. She was a regular contributor to makeup.com, and her articles and blog posts can be found on prevention.com, dailyglow.com, yahoo.com and huffingtonpost.com. Karina has worked onstaff at Cosmopolitan and YM, as well as being part of the original Sephora.com launch team

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