What Is Skin Made Off

The skin is the largest organ in the body, comprising about 15% of the body weight. The total skin surface of an adult ranges from 12 to 20 square feet. In terms of chemical composition, the skin is about 70% water, 25% protein and 2% lipids. The remainder includes trace minerals, acids and numerous other chemicals.

The skin consists of three main layers: epidermis, dermis and subcutaneous tissue.

The Epidermis

The epidermis is the topmost layer of the skin. It is the first barrier between you and the outside world. The total thickness of the epidermis is usually about 0.5 - 1 mm. The uppermost layer of the epidermis, called stratum corneum consists mainly of dead cells, hardened proteins and lipids, forming a protective crust. Dead cells continuously shed and are replaced by new ones coming from below. The skin completely renews itself every 3 - 5 weeks.

Another significant group of cells in the epidermis produce melanin, the pigment responsible for skin tone and colour.
The condition of epidermis determines how "fresh" your skin looks and also how well your skin absorbs and holds moisture. Wrinkles, however, are formed in lower layers.

The Dermis

The dermis is the middle layer of the skin located between the epidermis and subcutaneous tissue. It is the thickest of the skin layers and comprises a tight, sturdy mesh of collagen and elastin fibers. Both collagen and elastin are critically important skin proteins: collagen is responsible for the structural support and elastin for the resilience of the skin.

The dermis also contains capillaries (tiny blood vessels) and lymph nodes (depots of immune cells). The former are important for oxygenating and nourishing the skin, and the latter for protecting it from invading microorganisms.

Finally, the dermis contains sebaceous glands, sweat glands, hair follicles as well as a relatively small number of nerve and muscle cells. Sebaceous glands, located around hair follicles, are of particular importance for skin health as they produce sebum, an oily protective substance that lubricates and waterproofs the skin and hair. When sebaceous gland produce too little sebum, as is common in older people, the skin becomes excessively dry and more prone to wrinkling. Conversely, overproduction or improper composition of sebum, as is common in adolescents, often leads to acne.

The dermis is the layer responsible for the skin's structural integrity, elasticity and resilience. Wrinkles arise and develop in the dermis. Therefore, an anti-wrinkle treatment has a chance to succeed only if it can reach as deep as the dermis.

Subcutaneous Tissue

Subcutaneous tissue is the innermost layer of the skin located under the dermis and consisting mainly of fat. Subcutaneous fat acts as a shock absorber and heat insulator, protecting underlying tissues from cold and mechanical trauma. The loss of subcutaneous tissue, often occurring with age, leads to facial sag and accentuates wrinkles.