How many times should I reapply sunblock?
Sunblock reapplication depends on your activity level. If you plan on spending lots of time outside being active, you should reapply every two hours. On a sunny summer day, Dr. Levine recommends SPF 45. Beyond the SPF (which only measures the amount of UVB), try using a physical blocker like titanium dioxide or zinc oxide (both block all light, including UVA).
And remember, sunblock should be a year-round beauty tool. Its application is especially important in winter months when the snow starts working as a sun reflector.
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