Your Official Sun Care Cheat Sheet

An abbreviation for "sun protection factor," SPF refers to the rating system by which we determine how much protection we're getting against UVB rays. According to The Skin Cancer Foundation, "The SPF number tells you how long the sun's UV radiation would take to redden your skin when using the product exactly as directed versus the amount of time without any sunscreen. So ideally, with SPF 30 it would take you 30 times longer to burn than if you weren't wearing sunscreen."

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