The Structure of the Skin

The skin is made up of about 70% water, 25% protein, 2% lipids, and some other elements and minerals. When you realize that the skin is mostly water you understand how important it is to keep the skin moisturized and hydrated.

Layers of the skin.

You may know that the skin is actually several layers of different types of skin cells but this can be difficult for many to picture since these layers and cells are so small. Each layer however is different from the rest and each has a certain purpose or function which explains their composition.

The epidermis is the outermost layer of skin and the cell are harder and more flattened than those underneath it. The epidermis is thicker and harder on the soles of the feet and palms of the hand because these of course come into contact with things so they need to be stronger. There are actually four layers in the epidermis itself, all of which together are no thicker than a pencil line.

This layer produces collagen and elastin, two protein substances that are important for skin's health. Elastin is what gives skin its stretchiness; as we age this substance breaks down and this is what causes sagging skin that doesn't seem to be as firm as it once was. Those that are very overweight and obese can wear out this elastin so that their skin sags after they lose weight. Collagen is what plumps up skin and helps to keep it soft and supple. A lack of collagen means the skin feels dry and brittle.

Important: Collagen and elastin are going to be important elements when it comes to preventing and correcting stretch marks. Realizing what these substances are and how and where they occur is the first step toward correcting this problem.

The layers underneath the surface have new cells which aren't as hard and which are always pushing up on the top layer of the skin. Unlike snakes and other animals that shed their skin in large pieces, humans actually shed skin cell by cell as these lower layers push up and cause these outermost layers to fall away.

Humans also lose a lot of hydration through this process. Water is carried on the skin for its own health so as these layers push up they take water and hydration with them, which then of course evaporates into the air.

The dermis is the next layer of skin under the epidermis. The dermis contains the more functioning parts of the skin, including the sweat glands, oil glands, hair follicles, and nerve endings. If you cut yourself enough to feel pain, you've reached the dermis. Smaller surface cuts and abrasions on the epidermis or outer layer of skin don't always hurt as this layer is tougher.

Source: http://www.netdoctor.co.uk/skin_hair/skin_structure_003740.htm