SPF 100 Versus SPF 30: The Numbers, Honestly Compared
SPF 30 filters about 97 percent of UVB and SPF 100 about 99 percent — and the real-world gap lives in how much you actually apply.
Written by Nikki RobertsHealth advice that shows its working.
Evidence-checked guidance written by people who cite their sources, reviewed before it goes up, and dated so readers know when it was last true.
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