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Sun protection: Know your numbers

yellow and white striped sun hat with yellow sunglasses sitting on the edge of the hat with yellow background

Many of us give little thought to protecting our skin from the sun throughout the year. But, the effects of the sun can be exceptionally damaging. One of the best ways to protect your skin is by using sunscreen. To help you select the right sunscreen, here are a few tips:

Sun Protection Factor (SPF)
SPF is the key number you will find on the label. The SPF of any sunscreen reflects its ability to protect your skin from rays that cause sunburn. For example:

  • SPF 15 blocks 93 percent of UVB rays (this is the minimum SPF that dermatologists recommend).

  • SPF 30 blocks 97 percent of UVB rays.

  • SPF 50 blocks 98 percent of UVB rays.

  • SPF 100 blocks 99 percent of UVB rays.

Here’s what you need to know in regard to applying and reapplying sunscreen:

  • Apply sunscreen at least 30 minutes before you head outside.

  • Sunscreen application is effective for approximately two hours, according to the FDA.

Water Resistance
The FDA bans the use of “waterproof ” or “sweatproof ” on product labels, but it does endorse one of two ratings in regard to how long sunscreen will last during swimming or activity that causes significant perspiration. These ratings are either 40 or 80 minutes. 

Sunscreen expiration dates
Just like the milk in your fridge, sunscreens have an expiration date as well. Make sure to pay attention to this date before applying. To help keep sunscreen “fresh,” be sure to keep it in a cool, dry place.

With all the sunscreens and advice out there, it can be difficult to know the best way to protect your skin. Using the numerical guide above can help you cut through the confusion. 

Source: skincancer.org

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