(NBC) - As many Americans get ready to hit the beach or pool this weekend, experts from the Environmental Working Group say there's a good chance your sunscreen won't protect you from the sun's harmful rays.
Experts from the non-profit organization studied 500 beach and sport sunscreens and say fewer than 10 percent made the grade.
The main problem was an increase in high SPF sunscreens. Researchers said these are tricky because users don't re-apply the sunscreen as often as they should, thinking the high sun protection factor lasts longer than it really does.
They also said Vitamin A, which is often added to sunscreens to slow skin aging, may actually accelerate skin damage and increase the risk for cancer if the skin is exposed to sunlight.
This theory is still under review and has only been tested in mice.
Experts recommend looking for products that contain the minerals zinc or titanium; however, the best way to protect your skin from the sun is to wear hats and clothing or stay in the shade.