The skin is a structure of our organism wisely designed to protect us from the aggressions that it receives from the outside
In particular, it has a series of defense mechanisms that safeguard us against the action of solar rays .
These mechanisms are basically three:
The melanin , whose synthesis – best natural skin care promoted by solar ultraviolet mainly type A – a barrier that prevents vital largely, the skin being burned by sunlight. It also acts by neutralizing the free radicals released by cells that have been damaged by solar radiation.
The presence of melanin in the skin may be ‘natural’, without a previous stimulation, or it may occur after the redness produced by the sunburn.
This ability to synthesize melanin is genetically determined and is a racial factor, with logical variations between people of the same race.
Depending on the ability to synthesize melanin, 6 types of skins included in the scale ofphototypes of Parrish. The smaller the phototype, the greater the vulnerability to the negative effects of solar radiation.
However, being dark is not a guarantee of absolute protection against the harmful effects of the sun, it only protects it from burns. Melanin does not prevent the damages that in the medium and long term exert the rays of the sun on the skin.
The sweat , whose secretion is stimulated by the heating effect of ultraviolet rays , containing urocanic acid which acts as a sunscreen for its ability to absorb ultraviolet radiation.
The horny layer , whose thickening is induced by solar radiation and hinders the penetration of ultraviolet rays. In fact, Asian individuals, although less able to synthesize melanin than Caucasians, are more protected by the greater thickness of their stratum corneum, which explains the lower incidence of skin cancers.