The skin is the largest organ of the body and is comprised of three layers. Each layer performs important tasks and is needed to keep the body healthy. Dermatologists are physicians that specialize in the care and treatment of the skin.
The top or outermost layer of skin – the layer you can see – is called the epidermis. The epidermal skin layer ranges from extremely thick to very thin, depending on its location on the body.
This epidermis is mostly made up of flat, scale-like squamous cells and performs a number of functions, including:
- Protection – the epidermis protects the body from germs and helps prevent infection
- Color – melanocytes in the epidermal layer produce melanin, the pigment responsible for creating skin color. Melanin also helps protect skin from sun damage. The number of melanocytes increases with sun exposure
- Production of new skin cells – new skin cells are constantly being made at the bottom of the epidermis. As old skin cells die and slough off, new cells replace them. The average person sheds approximately 9 pounds of skin cells each year.
The middle layer of skin is known as the dermis. The dermis is responsible for important functions, such as:
- Sweat production – sweat glands in the dermis make sweat and send it through a series of tubes out to skin pores. Sweat cools the body and gets rid of impurities
- Sensation – nerve endings in the dermis carry messages to the brain that help you recognize various sensations like touch, temperature and pain
- Hair growth –hair roots are located in the middle layer of skin
- Oil production – sebaceous oil glands produce oil to soften skin, but when the glands make too much oil, pimples can develop. Collagen and elastin proteins in the dermis provide support and elasticity. With age, collagen production is reduced and wrinkles develop.
- Blood circulation – blood vessels carry fresh blood to the skin and take away impurities and waste products. Blood vessels also help to regulate body temperature.
The deepest layer of the skin is made up of fat. The connective tissue in fat helps attach the dermis to the muscles and bone and pads them to prevent injury. Fat also provides insulation and regulates body temperature. Nerve cells and blood vessels in the dermis pass through the fat and continue out to the rest of the body.
Keeping Skin Healthy
Each layer of skin plays an important role. To keep skin healthy, dermatologists recommend washing with a gentle, fragrance-free soap; practicing healthful eating; moisturizing daily and applying sunscreen before going outdoors.