Choose the larger the sunscreen cosmetics is prevented bask in, the better?

Rumor summer many people choose sunscreen cosmetics such as cosmetics, think that the larger the prevent bask in, the better. There are also some people think that bask in multiples can be stacked like add, such as skin cream SPF15 sunscreen SPF18, together with is equivalent to SPF33. Is it true? Sunscreen is prevented bask in multiples can't stack yuan-hong li, director of the China medical university first affiliated hospital dermatologist, physicians, sunscreen products on the market at present coefficient ranged from 6 to 60 times. Prevent bask in general, the larger, the better the results, but the product with high multiples often contains a lot of physical or chemical sunscreen, some big to cutaneous stimulation, easily clogged pores, acne and acne even develop. So don't blindly choose sunscreen multiples larger products. Second, sunscreen multiples can't stack, but the highest ratio shall prevail. In addition, some people mistakenly think that the larger the sunscreen, sunscreen the longer it will be. Actually, sunscreen ratio represents the sunscreen is prevented bask in ability, has nothing to do with the duration of the sunscreen. When sunscreen after uv absorber suck full of sunshine, loses the effective protection. Therefore, in general, chemical sunscreen need every 2 - Three hours added it again. Physical sunscreen every 3 - 4 hours added it again. Most sunscreens are the combination of chemical and physical sunscreen sunscreen, so generally speaking, at intervals of about three hours to complement afresh sunscreen.