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How to choose a natural sunscreen
Look for 10 percent zinc oxide or titanium dioxide.
Natural sunscreens often use ingredients that physically, rather than chemically, block the sun. Because these don't offer a high spf on their own, you need to make sure they have a high enough concentration in the sunscreen to actually block the sun's uv rays.
Choose a sunscreen that has a 10 percent or higher concentration of zinc oxide or titanium dioxide. These two ingredients are the only fda-approved ingredients for blocking the sun that are often used in natural sunscreens.