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SPF Sunscreen Rankings Explained

SPF 15, SPF 30, SPF 45: Seriously, What's the Diff?

The snow is gone and Spring is finally here. The warmth of the sun may feel sweet on your skin, but do remember that those rays can cause premature skin aging and skin cancer. Thank goodness for sunscreen! Shopping for protection from the sun can be more than a bit confusing with SPF ratings that range from 2 to 60.

For starters, SPF stands for sun protection factor, but the numbers don't refer to how long you can spend outside without getting a sunburn, they refer to the amount of UVB protection the product offers. UVB rays were once thought to be the sole type of sun ray that caused skin cancer. Sunscreens with SPF 15 filter out 93 percent of UVB rays; SPF 30 filters out 97 percent. The thing is, wearing a sunscreen with a higher number, such as SPF 45, won't allow you to stay out longer, since the effectiveness of sunscreen decreases over time. Plus if you're active, either swimming or sweating in the sun, the moisture can wash sunscreen away, leaving your skin less protected. So it's a good idea to reapply sunscreen every two hours, just to be sure. Don't wait to see if your skin is turning red before reapplying since a sunburn may take up to 24 hours to appear fully.


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