While UV-B rays cause sunburn , UV-A rays penetrate deeper into the skin, lowering our resistance to skin cancers and causing skin to age. The SPF number or Sun Protection Factor on sunscreens refers only to UV-B protection . … Public interest groups are currently asking the FDA to declare all currently available sunscreen products with nanoparticles a potential hazard to public health. Until complete safety -assessments are made, I recommend steering clear of products …
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Sensible Sun Exposure
