All About Skin

Submitted by Anonymous (not verified) on

Our skin is our largest organ, with approximately 20 square feet.  The skin has a major function of protecting our insides acting as a protective barrier.  Learning more about your skin and how it operates will teach you how to treat it properly.

Skin Layers

There are three layers of the skin including the epidermis, dermis, and subcutaneous tissue. 

            Epidermis – This is the outermost layer of the skin that gives the skin its waterproof barrier and its tone.  These skin cells are shed continuously and new ones take their place.  The most common skin cell type is the keratinocyte, whose job is to act as a barrier against bacteria, fungi, viruses, heat, and UV.  The epidermis contains no blood vessels and it contains melanin, which is what gives us our lovely tans.

            Dermis – This middle layer of the skin is responsible for making sweat and oil.  It also provides sensations and blood to the skin.  This layer also grows hair.  It is mostly comprised of connective tissue.  It protects the body from stress and skin elasticity and skin strength.  If the dermis gets stretched too much, like during pregnancy, you may end up with stretch marks.  The pressure, heat, and pain receptors are also found in the dermis.

            Subcutaneous tissue – The main roles of this tissue is to attach to the dermis and underlying bone.  It also controls body temperature and storage of fat.  The fat layer acts as a protective barrier for our bones and muscles.

Functions

The functions of the skin include protection, storage, sensation, water loss, water resistance, and thermoregulation.  The skin functions as part of the immune system.  The storage function involves storing fats and water.  Sensations are due to nerve endings that detect temperature, pressure, vibration, touch, and even injury.  The skin also controls water loss, so it can keep you hydrated or it can allow water to escape to cool your body down.  Thermoregulation produces sweat and dilates blood vessels and helps keep the skin cool.  Goosebumps are produced by blood vessel constriction in the skin that helps us retain heat.

Skin Color

Human skin color varies in color due to a pigment known as melanin.  Melanin’s primary role is to protect the skin from damaging UV light from the sun that can cause cancer.  When the skin is exposed to UV light, you get a suntan because the melanocytes start producing melanin.  Those that live closer to the equator tend to have higher levels of melanin and darker skin, as you live closer to the poles you tend to have lighter skin.  In general, females have lighter skin than males, mainly due to pregnancy and the need for calcium and vitamin D, which is produced when exposed to the sun.

Our skin is a very complex organ that has a wide range of roles in our body.  We need it to protect us from the elements, help us maintain the right temperature and to let us know when there is pressure, temperature, or pain issues invading our lives.