How long sunscreen work

So does that mean SPF 60 is twice as protective, or lasts twice as long? Nope, according to the experts. An SPF of 30, when applied in the appropriate amount, will block out about 96 percent of the sunburn-causing UVB rays from the sun, Garner says. As you go up from there, you only see a very small difference about 98 percent with SPF 50 and still under 99 percent with SPF 75 -- there's no way to block out percent of the sun's rays with sunscreen.

If you feel more comfortable with those extra couple of percentage points, go for it. But it doesn't change how often you'll need to reapply or how long you can be in the sun. Your sunscreen can't block out percent of the sun's UVB rays, and it shouldn't be your only defense against sun damage. The rest of the work -- wearing a hat, sunglasses and protective clothing and avoiding the sun during the most intense hours -- is up to you. Remember, too, that sunscreen isn't a free pass to spend the day baking in the sun.

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Part of HuffPost Wellness. All rights reserved. You've been using the same bottle for the past three summers. You count on the SPF in your makeup to do the trick. You count on waterproof sunscreen when you're swimming. You only apply sunscreen on sunny days. Even SPF needs to be reapplied every two hours to provide the maximum benefit to your skin. Both types can increase your risk of skin cancer. Focus on Sun-Exposed Areas Not sure if you applied a thick enough layer of sunscreen?

Reapply it before you go outside. The tops of ears are another frequently missed spot that get a lot of sun exposure. The bottom line? Reapply your sunscreen every two hours or sooner. Your skin will thank you for it. References Young, Antony R et al.

Close Cart. There are errors with your cart:. Remove Item. Free Gift. Add Ons. Looking for more? Baumann suggests. Above all, find a sunscreen you love, especially for your face since reapplying here can be a bit tricky. There are tinted sunscreens that offer light coverage, moisturizers with SPF if you like to go bare-faced, and powder sunscreens that make reapplying over makeup easier than ever.

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