The importance of applying sunscreen cannot be emphasized enough, but do you know just how much sunscreen you should be applying each time? Experts recommend Lotions, foams and sprays that prevent sunburns are tested at 2 milligrams per SQUARE CENTIMETER of skin to determine the sun protection factor, or SPF. The Wall Street Journal said that because people tend to use roughly half as much sunscreen as recommended, some research has concluded that to ensure proper coverage, it should be applied twice.
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