The skin gets damaged by UV light even in the dark, ironically as it may seem

Contrary to popular belief, much of the damage inflicted to the skin by harmful ultraviolet (UV) light occurs hours after exposure to the sun, even when you’re sitting comfortably asleep in your dark bedroom. The Yale University research also made a startling find: melanin – the pigment that gives human skin and hair its colour – has both carcinogenic and protective effects. This double standard should be taken into consideration from now on when discussing UV exposure, but also when looking for new treatments to skin cancers like melanoma.