Skin has many functions. A as protective shield, the skin defends almost the entire body from a host of threats including pathogenic microorganisms, atmospheric agents and radiation. Skin perfectly isolates organs and internal systems with its complex covering, adjusting internal temperature like a sophisticated thermostat. It protects against moisture depletion thanks to its superficial hydrolipidic film. Skin is home to the recetors that create our sense of touch. Skin complexion reveals our age, race, state of health, even mood when we blush turn pale from anxiety or fear. It is not an exaggeration to say that our skin is a window into our psycho-physical well-being.
The skin, thanks to the complexity of its structure, performs many functions. Here are the main ones:
- BARRIER FUNCTION
The skin represents a natural barrier to the external environment thanks to the presence of a hydrolipidic film on the skin surface and the stratum corneum that ensures the body an effective defense against external and internal threats. The hydrolipidic film is an invisible shield composed of water and fats produced by the sweat and sebaceous glands in the the outermost layer of the skin and covers the surface of the epidermis. Water and sebum emulsify on the stratum corneum (the outermost layer of the epidermis) to form a barrier that preserves hydration levels in the skin and defends it from external attacks.
Keeping the skin’s natural hydrolipidic film intact is a fundamental requirement to ensure the correct balance of the skin.
- PROTECTIVE FUNCTION – The skin protects the internal structures of the body, thanks to the flexibility of skin tissues and the texture of elastic fibers.
- THERMOREGULATORY FUNCTION – The skin regulates body temperature thanks to a complex system of dilation and constriction of blood vessels (veins and capillaries) and the mechanism of sweating.
- PURIFYING FUNCTION – The skin performs a purification function thanks to the presence of sweat glands and sebaceous glands in the dermis that allow the elimination of toxins, sweat, urea and other waste substances of the organism.
- DEPOSIT FUNCTION – Fat reserves accumulate the deepest layer of the skin (hypodermis). The most plentiful type is called subcutaneous fat that. This should not be confused with visceral fat that accumulates in the presence of excess weight or obesity and is associated with a high risk of cardio-vascular diseases.
- SENSORY FUNCTION – There is a large amount of sensory nerve receptors in the skin responsible for tactile function (sense of touch). These receptors transmit signals (hot, cold, smooth, rough, pressure changes, pain, etc.) to the spinal cord and brainstem. From here, nerve impulses travel to and from the upper areas of the brain. Some receptors, the deeper ones, are enclosed inside a connective tissue capsule (corpuscles of Meissner, Ruffini, Pacini), other more superficial ones, are not. There are about 1 million nerve fibers that serve the skin. Skin sensory perception has a protective function and is of fundamental importance to how we interact with others.
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