How much sun block should I use and how often should I use it to protect my skin?

How much sun block should I use and how often should I use it to protect my skin?

Harry Saperstein, MD, FAAD (Dermatologist, Clinical Assoc. Professor, Medicine, Private Practice and UCLA) gives expert video advice on: How effective is sun block?; How much sun block should I use and how often should I use it to protect my skin?; Why is it important to keep a close watch on atypical moles? and more...

Sun block needs to be applied an hour before you go outside, and it needs to be applied in probably double the quantity that most people apply it. The SPF factor, which is the sun protective factor, relates to the ability the sun block has to protect itself against ultraviolet B rays or the burning rays. In general, 15 is adequate for city wear. 30 would be more appropriate if you find yourself out for a long period of time in the midday, and even some of the higher numbers would be appropriate if you are our doing some sort of sun seeking behaviour or are in an area where you cannot avoid it, such as you are playing beach volleyball. These do not address, however, ultraviolet A exposure. The newer sun blocks do have ultraviolet A protection and they are important to look for. It will say on the sun block “full spectrum protection”. It might even say ultraviolet A and ultraviolet B protection. Most of the newer sun blocks will do so. Some of the things you want to look for are avobenzone, zinc, and titanium, and there are some newer additions from Europe that are coming out in this country that can even actually boost the sun protective factor.