We know some of the risks (and the list is long): sunburn, allergies, skin ageing, ,... But we sometimes ignore the reasons, although they are crucial. UVB-UVA radiation as well as the high-energy blue light that our skin absorbs during prolonged exposure causes real skin damage. UVB rays do not penetrate far beyond the epidermis, whereas UVA rays penetrate more deeply. Their damage is therefore less visible and can be detected in the long term. As an extension of UVA, blue HEV light causes deep cellular damage to the skin over the long term by attacking all the cellular components: lipids, proteins and DNA.