sun protection factor

Most commonly seen as SPF followed by a number, it is a rating system assigned to a product that identifies the amount of time it can protect the skin from sunburn or from turning pink or red when exposed to sun. In the United States, SPF ratings are regulated by the Fod & Drug Administration. Because sunburn results from UVB radiation, not UVA radiation, SPF is primarily a measure of UVB protection; however, sunscreens rated for broad spectrum protection can protect from UVA rays, too.


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About the Experts

Paula Begoun is the best-selling author of 20 books about skincare and makeup. She is known worldwide as The Cosmetics Cop and creator of Paula’s Choice Skincare. Paula’s expertise has led to hundreds of appearances on national and international radio, print, and television including:

The Paula's Choice Research Team is dedicated to busting beauty myths and providing expert advice that solves your skincare frustrations so you can have the best skin of your life!