You're not alone if you've wound up with a sunburn even though you took time to apply SPF. Experts recommend wearing sunscreen daily, but don't always provide information on how to use it correctly.
How to Apply Sunscreen
Physical and chemical sunscreens work a bit differently. Chemical sunscreen has chemical formulas that work by absorbing into the skin. It needs to be applied at least 10 minutes before sun exposure to give it ample time to sink in. Physical sunscreen, sometimes called sunblock, provides physical defense that uses minerals to block or reflect UV rays so they don’t penetrate the skin. They start working the moment you put it on.
Both products are applied the same way. The only difference is timing.
- Shake the bottle well before you squeeze any sunblock or sunscreen out. This mixes up all the particles and distributes them evenly in the container.
- An adult should use about 35 milliliters or 1 ounce (about 2 tablespoons) of sunscreen to cover their entire body, which is the same amount that would fit into a shot glass. It's also about the same as an adult handful. Remember, most people don't apply enough sunscreen, so using more than you think you should is okay.
- Cover all of your skin that will be exposed to the sun. This includes often neglected areas like your back, ears, behind your knees, and legs.
- Continue to reapply throughout the day. If you've been in the sun for 30 minutes, you might want to reapply more sunscreen to get any places you might have missed. Reapply 1 ounce of sunscreen at least every 2 hours. Constantly reapply 1 ounce of sunscreen after swimming, sweating, or toweling off.
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How to Get The Most Out of Sunscreen
Sunscreen application isn't a once-and-done deal, and just because you're wearing sunscreen doesn't mean you can't get burned. Get the maximum sun protection possible by following these tips:
- Always reapply. Reapplication is just as important as the first application. Set an alarm to help you remember.
- Apply more sunscreen than you should. Better to apply too much than not enough.
- Wearing sunscreen doesn’t mean you’re immune to sunburn. You’re more likely to get a sunburn when the sun’s rays are most intense, from 10 a.m. to 4 p.m.
- Watch your SPF. The SPF number tells you the percentage of the sun’s UVB rays that can be blocked by sunscreen/sunblock. For example, SPF 30 blocks 97% of the sun’s UVB rays, whereas SPF 50 blocks 98% of the sun’s UVB rays. No SPF level blocks 100% of UVB rays.
- Insect repellents can reduce a sunscreen’s SPF by up to 30%. If you’re using sunscreen and insect repellent together, use them as separate products rather than a combination product, use a higher SPF, and reapply more often.
