The skin is one of the largest organs of the human body: in fact, if stretched out completely it can reach 2 square metres and in terms of weight it makes up 16% of the total body weight. Its main function is to protect organs and internal tissues from aggressions of the “world outside” and therefore constitutes a physical barrier covering the entire body surface. It plays a fundamental role in protecting the body from heat and cold (thermoregulatory function), from injuries and from aggressions of external pathogenic agents. Last but not least, it is seat of nerve endings of the sense of touch.
The surface of the skin is not uniform: it has a very complex design that varies due to the presence of parallel patterns along its surface that determine, particularly on the fingertips, typical figurations (called “fingerprints”) that vary from individual to individual. The skin is formed by two layers: the epidermis and the dermis. In the human species, skin colour depends on many variables (thickness of the corneous layer, level of blood perfusion, presence and optical absorption of melanin, vitamin A dimer, hemoglobin). For this reason, colour varies not only according to the ethnical group but also with individuals and, even though in small nuances, it also changes in different body regions of the same individual.
The epidermis is the outer part of the skin, formed by several layers of cells, of which the most external ones are basically dead but resistant to external agents. The principal functions of this layer of skin are: to form a physical barrier against external agents; prevent dehydration of the body; prevent penetration of bacteria or other pathogenic agents; protect the body from sunburns by means of special cells called melanocytes, which produce a protein called melanin, responsible for skin coloration; rapidly repair the skin in case of injuries.
The dermis is the layer right under the epidermis. Its principal function is to support and nourish the skin. In fact, it contains blood vessels carrying nutrients to the skin itself, as well as the sebaceous and sweat glands, in charge of regulating the body temperature; nerve endings that receive impulses coming through the epidermis; hair roots.
The skin is a very delicate organ that can incur several problems, either injuries or irritations. The most frequent are pressure sores, ulcerations, burns, injuries, bruises, erythema, abrasions, cuts, etc. The skin undoubtedly performs essential functions for the health and well-being of the entire organism: it is therefore important to maintain its integrity and functionality adopting correct hygiene habits that include specific cleaners and, in case of pathologic events, using appropriate natural remedies.