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Don’t get burned–not all sunscreens are created equal

With the sun-drenched days of summer rapidly approaching, dermatologists are calling for anyone who spends time outside apply liberal amounts of sunscreen for protection.

Arnold Gurevitch, USC professor and chief the division of dermatology, said the type of sunscreen-whether cream, oil or lotion-generally doesn’t matter.

But it should have a sun protection factor (SPF) of between 15 and 30.

SPF ratings are based on how many minutes of sun a person can tolerate without burning during their first significant exposure of the summer. A SPF 2 rating will double the length of time a person a person can stay in the sun without burning.

A person who normally burns within 30 minutes could delay burning by six hours by using an SPF 12 sunscreen.

In general, sunscreens with higher SPF numbers offer correspondingly higher protection, but at levels above SPF 30 the distinctions become meaningless, Gurevitch said.

“Anything over 30 is probably overkill because there aren’t that many hours of sunlight in the day. Anything between 15 and 30 is reasonable,” he said.

Still, Gurevitch emphasized that sunscreens should not be considered a license to tan.

“People think that since they wear sunscreen, ‘Hey, I can stay out in the sun all day.’ But that’s not the idea. Sunscreens aren’t 100 percent effective so they shouldn’t be used to justify staying out longer,” he said.

Children are especially vulnerable to sun exposure and childhood sunburns are linked with a higher incidence of certain cancers later in life.

Sunscreens made for children have the same active ingredients as adult versions, so either will offer adequate protection, he said.

Gurevitch also said that people who go swimming or sweat substantially should reapply lotion, even if it’s waterproof, to ensure they’re protected.

Don’t get burned–not all sunscreens are created equal

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