One should apply sunscreen every day to exposed skin, even if you are not going to be outside in the sun. While some of the suns ultraviolet rays cannot penetrate glass windows, some can, leaving you prone to these damaging effects if unprotected.
For days when you will be indoors, apply sunscreen on the areas not covered by clothing, such as the face and hands. Sunscreens can be applied under makeup, or alternatively, there are many cosmetic products available that contain sunscreens for daily use. Sun protection is the best means of preventing premature aging and skin cancer.
Don’t reserve the use of sunscreen only for sunny days. Even on a cloudy day, up to 80 percent of the sun’s ultraviolet rays can pass through the clouds. In addition, sand reflects 25 percent of the sun’s rays and snow reflects 80 percent of the sun’s rays.