This section provides comprehensive information about the four purposes of
the skin.
- Protection
The skin protects against infectious agents and mechanical or physical injury.
- Sensation
The skin can sense pain, itch, light, touch, heat, and cold through specialized
nerve fibers. Specialized receptors contribute to tactile (touch) sensations
and identification of noxious substances.
- Metabolism
The skin is the site of Vitamin D synthesis. It also reflects the internal
environment. For example, cancer patients frequently have depressions on
the face and loose skin because of fat loss.
- Communication
The skin may reflect one's condition. For example, a yellow skin indicates
jaundice. Or the skin may reflect a person's mood or feelings, as in the
red, rough skin around the eyes that indicate that a person has been crying.
Various facial expressions communicate mood, acceptance, rejection, sorrow,
happiness, etc.
Skin: A Two-way barrier
The skin not only prevents noxious substances from getting in, but also prevents
excessive loss of water, electrolytes, and other body constituents. The body
would rapidly dehydrate without a tough, semi-permeable skin (i.e., following
severe burns.)
