The skin is the largest organ in the body, accounting for 16 per cent of your total body weight.
There are three basic layers in the skin - the epidermis, the dermis and the hypodermis. The epidermis is the outer layer which absorbs atmospheric toxins and ultraviolet rays from the sun. The outermost layers of the epidermis are dead and are continuously shed. The skin also synthesizes vitamin D.
The cells in the epidermis regenerate more slowly as we age (every two weeks at age 20 and every month or so from age 40 onwards) and many anti-ageing skin care products focus on speeding up cell regeneration as a way to enhance the skin.
In between the epidermis and the dermis lies the so-called basal layer which provides oxygen and nutrients to cells in the regeneration process. Collagen and elastin are protein fibres in the dermis which make the skin resilient. Production of collagen and elastin declines with age, causing the skin to thin out and wrinkle. Many anti-ageing skin products claim to add collagen and elastin to the skin.
The sweat and oil-secreting glands also diminish with age which makes the skin prone to dryness. Most skin products contain a water/oil emulsion which prevents the evaporation of water from the skin.
The sun causes the most damage to the skin by interfering with the production of pigment, melanin which can later generate age spots. The sun also toughens the epidermis causing a leathery, taut and uneven texture to the surface of the skin. By weakening the dermis layer, it can also interfere with blood production and cause burst capillaries or spider veins.