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Structure and function of the Skin


The skin often mirrors the health of the whole body. The skin is the largest organ of the body and is as indispensable as the body's other major organs. A radiant clear complexion begins with proper nutrition, efficient digestion and assimilation of nutrients by the body and regular elimination.

The skin consists of four distinct layers: the epidermis, the basement membrane zone, the dermis and the subcutaneous layer. The skin is an ever-changing organ that contains many specialized cells and structures. The skin functions as a protective barrier that interfaces with a sometimes-hostile environment. The skin is the ultimate vessel for the human body; it receives and transports, accepts and expels according to the body's needs. It is container, defender, regulator, breather, feeler, and adaptor. But success in these roles is not accomplished automatically. As sturdy as it is, the skin requires attention and maintenance to function properly. Without such care, the complex organization of the skin breaks down, making it and the body it protects susceptible to injury and disease.


Epidermis

The epidermis is the outermost layer and is a microscopic 0.2 mm (8/1000 inch) thick on the face. The surface consists of dead cells which are in the process of flaking away and new ones which are growing to take their place. Between the epidermis and dermis lies the basal layer, where new epidermal cells are formed and progress to the surface. It takes approximately twenty-eight days for a new cell to reach the top.

Dermis

The dermis is usually 1.8 mm (7/1000) thick. It is composed of a fibrous protein called collagen, elastin, which makes the skin supple, and a network of blood vessels, nerves, oil and sweat glands, pores and hair follicles.

Hypodermis

The hypodermis is the tissue beneath both epidermis and this dermis. It contains muscles, veins and fat -cells and its thickness varies according to the part of the bodies. The sebum and sweat produced by the oil and sweat glands in the dermis form a hydrolipidic film on the skin. This film, known as the 'acid mantle' lubricates the skin's surface, helps to repel bacteria and protects against irritation. The acid mantle maintains the skin's slightly acid (pH) level. It takes one to two hours for the skin to return to its normal pH level after washing. Harsh cleansers, such as soaps, reduce the removal process. It is the activity of the sebaceous (oil-producing) glands that determine your skin type. Activity in the T-Zone may be greater than elsewhere.

One of the greatest treasures that a woman or a man can have is healthy, radiant skin. A beautiful complexion and glorious body skin are a reflection of our personal life-style practices. If the balanced of the skin becomes disturbed especially through poor nutrition the functions associated with the skin cells cannot act in a balanced manner and can result in dryness, excessive oiliness, and inability to protect against infectious organism. The most rigorously followed healthful living plan necessarily includes a nutritious diet, purewater, regular exercise in the fresh air, adequate rest and sleep, sensible stress management.
The function of the skin are as follows:

    * Physical barrier against friction and shearing forces
    * Protection against infection, chemicals, ultraviolet irradiation, particles
    * Prevention of excessive water loss or absorption
    * Ultraviolet-induced synthesis of vitamin D - Sensible exposure to sunlight synthesizes the production of vitamin D through interaction with ergosterol, a naturally occurring fat found in the skin. Vitamin D absorption helps metabolize calcium and phosphorous, which is important to bone and tooth health.
    * Temperature regulation - It is also very involved in maintaining the proper temperature for the body to function well.
    * Sensation (pain, touch and temperature)
    * Antigen presentation/immunological reactions/wound healing