STOP acting like u don't know this FACT (and if u don't for some insane reason, now you do!) -Photodamage created by the sun is the number-one cause of accelerated skin aging and skin cancer. In order to prevent this damage, it’s essential to “Protect” skin with sunscreen. SkinCeuticals offers PROPER Protection against photoaging and skin cancer. Take responsibility for your youth, you only get one and learn about the correct one for you.