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Sunscreen & Sun Protection
The SPF number on the bottle comes from a lab dose almost nobody applies, and it only measures UVB while UVA quietly drives most visible aging. Here we break down what the labels actually promise, how mineral filters really behave, and how to tell when your protection has failed.
3 guides
Inside the SPF Number: Why You Get a Fraction of It
The SPF on the bottle comes from a lab dose almost nobody applies. At real amounts, an SPF 50 can act like SPF 7. How much you actually need.
SPF vs. PA Rating: Which Number Actually Guards Against Skin Aging?
SPF only measures UVB protection. The PA rating measures UVA, which drives most visible aging. US labels don't require brands to disclose actual UVA coverage.
Mineral Sunscreen Doesn't Reflect UV Rays. Here's What It Actually Does.
That 'physical barrier' you've heard about? It's absorbing UV radiation, not bouncing it back. The science behind how mineral sunscreen actually works.