Before you can begin an optimal skin care regimen, you need to understand what your skin is composed of and what functions it performs. The skin is the largest organ in the body. It totals 1/6 of your body weight. It breathes, excretes, absorbs and protects. Imagine it as a huge waterproof, leak proof but permeable, super stretchable sack that keeps your insides in and the environment and germs out. It is subjected to heat, cold, rain, bacteria, sun and chemical and environmental pollution. Is it fun to be skin, or what?

One of the main functions of the skin is protection. It contains secretions that can kill bacteria and the pigment melanin provides a chemical pigment defense against ultraviolet light that can damage skin cells. Another important function of the skin is body temperature regulation. When it's exposed to cold temperature, the blood vessels in the dermis constrict. This allows the blood, which is warm, to bypass the skin. The skin then becomes the temperature of the cold that it is exposed to. Body heat is conserved since the blood vessels are not diverting heat to the skin anymore.

Our skin is a complex engineered covering, composed of cells, sweat pores and sebaceous (oil producing) glands. The skin is continually renewing and repairing itself. The surface layer of the skin is covered with a thin sheath of dead cells. These are continuously being pushed up to the surface from below. If the dead cells are not removed, they can reduce and even block the skin's effort to breathe and eliminate waste. Exfoliation removes these dead cells. The skin has a slightly acidic coating of oil at the surface. This coating protects the skin against some forms of bacteria.

Below the surface is a complex of sweat and oil glands, hair follicles, blood vessels, nerves and muscle tissue. These are held together by a tough connective tissue called collagen. Collagen is very important in determining the health of the skin. The relative health of the collagen determines the contour of the skin and how wrinkled and lined it is. Healthy collagen is often called soluble collagen because it can absorb and hold moisture. Below the collagen is a layer of fat and muscle, which provides some contour and acts as a cushion and as insulation.

The skin has three layers. The inner most layer is known as the lower dermis, the middle layer is called the dermis and the outer layer is known as the epidermis. All in all, the skin is truly one of the most amazing parts of the body.