What are Sunscreens?
Sunscreens prevent the sun’s ultraviolet (UV) radiation from reaching the skin. Two types of ultraviolet radiation, UVA and UVB, damage the skin and increase the risk of skin cancer.
UVB causes sunburn, while UVA rays, which penetrate the skin more deeply, are involved with wrinkling, leathering, sagging, and other effects of photoaging. They also exacerbate the carcinogenic effects of UVB rays, and increasingly are being seen as a cause of skin cancer on their own. Sunscreens vary in their ability to protect against UVA and UVB.
How does it work?
SPF stands for Sun Protection Factor and is a measure of a sunscreen’s ability to prevent UVB from damaging the skin. For instance, if it takes 20 minutes for unprotected (without sunscreen) skin to start turning red, using an SPF 15 sunscreen prevents reddening of the skin 15 times longer — about five hours. Read more