The evolution of humans is written on our skin. Beyond an identity signature, human skin color represents an example on how our species has been capable to adapt to different environments. We are all aware of the damaging effects of the sun and know the importance of protecting our skin, the largest organ of the body, constituting 16% of the human body’s weight (Figure 1). Ultraviolet (UV) radiation that reaches the Earth surface and to which we are exposed is composed of a mixture of UVA, which can penetrate deeply into the dermis and is responsible for the skin ageing, by provoking oxidative damage to proteins, DNA and cell membranes, and UVB, which only reaches the epidermis (the outermost layer of the skin) as it is partially absorbed in the atmosphere. This type of radiation is the most damaging one, as it can produce DNA and cell damage, and is largely responsible for sunburns. Furthermore, the painful sunburns that can occur without an adequate protection are a determini...
