An update on sunscreens

For the purposes of this article, sunscreen is a substance applied to the human skin to reduce transmission of components of the solar spectrum. What are the uses of such a sunscreen? One purpose, and a use a doctor may recommend a sunscreen for, is to minimise the damaging effects of sunlight (photoprotection). Another purpose, and one that is still a major use of sunscreens, is to avoid the discomfort of sunburn (a damaging effect) to allow greater sunlight exposure. This is sometimes done, but not always, with the purpose of attaining a tan (another marker of damage), which in some cultures is considered desirable.