IF IT’S EFFECTIVE WHY DO I NEED TO REAPPLY MY SUNSCREEN?
SKIN SHORT: Because even the best can get rubbed off.
MORE SKINFO: Your skin is a dynamic layer which absorbs some of your sunscreen’s ingredients, especially when the skin is really sweaty or wet. When this happens, less of the protective ingredients are on the surface of the skin where they need to be to do their job. Sunscreen is also removed by water immersion, toweling off and friction from clothing and physical activities. Best practice is to reapply every 1-2 hours.