Don't let the sun ruin your fun! Sunscreen can save your skin. Consumer Reports tested 20 sprays and lotions that claim to be water resistant and provide "broad spectrum" protection.

Jamie Kopf Consumer Reports, "Broad spectrum means they should protect against two types of ultraviolet rays: UVB rays which cause sunburn, and UVA rays which are linked to skin aging. Both types contribute to skin cancer." To test, Consumer Reports applied sunscreen to panelists' backs … and had them soak in a tub for 80 minutes.

Then the panelists were exposed to UVA rays … … or UVB, and the backs were examined a day later for color. It's protection from UVB rays that SPF quantifies. Lab testing 18 of the 20 sunscreens Consumer Reports tested came in below the SPF they promise on their packages, although except for two they did provide adequate protection. Jamie Kopf, "We can't say why our test results differ from the manufacturers'. In some cases we found the SPF was off by just a little. But two sunscreens were off by much more."

Beyond Coastal Natural claimed an SPF of 30, but testers found its SPF was below 15. Banana Boat Kids' SPF was also below 15, though it claimed SPF 50. The tests also found several of the sunscreens are less effective than others at protecting against UVA rays. Recommended products Consumer Reports did find seven sunscreens to recommend.

And it named two Best Buys. They're Equate Ultra Protection SPF 50 from Walmart for nine dollars … and the spray Up & Up Sport SPF 50 from Target for eight dollars.

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