What's the best sunscreen? Experts weigh in

SAN FRANCISCO (KGO) -- Summer's nearly here, which means fun in the sun. But no matter your age or skin color, if you're going to be outside longer than a few minutes, you'll need to use sunscreen to protect yourself against skin cancer and wrinkles.

In a partnership with Consumer Reports, 7 On Your Side's Michael Finney cuts through all the jargon to help find the best sunscreen for you.

"There are so many claims on sunscreen bottles, it can be really confusing to figure out which one to buy," said Trisha Calvo, Consumer Reports Health Editor.

SPF is a measure of how well a sunscreen guards against ultraviolet B rays from the sun, the chief cause of sunburn and a contributor to skin cancer.

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As part of Consumer Reports testing, sunscreen is applied to subjects' backs, and then they soak in a tub for 40 or 80 minutes, depending on the product's water-resistance claim.

The area is then exposed to UV B light. The next day, trained experts examine the area for redness. "In our sunscreen tests, we found that many sunscreens don't meet the SPF level printed on the package," said Susan Booth, Consumer Reports' project leader for sunscreens. "So Consumer Reports recommends buying a chemical sunscreen with an SPF 40 or higher," she said.

Two of Consumer Report's top best buy sunscreens are: Equate Walmart Sport Lotion SPF 50 and Trader Joe's Spray SPF 50.

If you're looking for a sunscreen containing mineral ingredients because you think they contain fewer chemicals, shop carefully. "In our sunscreen tests in recent years, we haven't found a mineral sunscreen that provides both top-notch protection and meets its labeled SPF," said Booth.

As for water resistant sunscreens: "Don't make the mistake of thinking that 'water resistant' means 'waterproof.' The minute you get into the water or start to sweat, the sunscreen starts to come off. So when you get out of the water, you have to re-apply," said Calvo.

To have a great sunburn free summer, Consumer Reports recommends applying sunscreen 15 minutes before you go out. Be sure to cover often overlooked spots, such as your ears, upper back, the backs of your hands and the tops of your feet. And re-apply every two hours, or after swimming or sweating.

And if you're wondering if that old half-used tube of sunscreen is still good, Consumer Reports says sunscreen is formulated to remain effective for at least three years. So toss that sunscreen if it's past its expiration date. And if you cannot find an expiration date, and don't remember when you bought that sunscreen, play it safe and buy a new one.

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