Thursday, November 08, 2007 7:22 PM
How many times should I reapply sun block? What SPF do I have to use?
Normally, sun block reapplication depends on your activity level. If you plan on spending lots of time outside being active you should be reapplying 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 physical blocker like titanium dioxide or zinc oxide (both block all light including UVA.)
And remember, sunblock should be a year round beauty tool. It's application is especially important in winter months when the snow starts working as a sun reflector.