Hair loss is very common in both men and women.
You or someone you love may be experiencing hair
Learning about normal hair growth is very important in
understanding hair loss.
This reference summary will help you understand
alopecia, the different types of hair loss, and their
Hair is made of a chemical called keratin, the same material that fingernails and
toenails are made of.
A specialized structure inside the skin called the papilla produces hair. A sac-like
structure called the follicle surrounds the papilla and the rest of the hair root that is
under the skin.
The shaft of the hair is on the outside of the body, sticking out of
The shaft has 3 layers.
• The cuticle—the outer layer.
• The cortex—the middle layer.
• The medulla—the center of the hair.
Hair color depends on different pigments in the cortex. As we
grow older, pigment gradually stops being produced, resulting in
gray or white hair.
This document is a summary of what appears on screen in X-PlainTM. It is for informational purposes and is not intended to be a substitute for the advice
of a doctor or healthcare professional or a recommendation for any particular treatment plan. Like any printed material, it may become out of date over
time. It is important that you rely on the advice of a doctor or a healthcare professional for your specific condition.
©1995-2008, The Patient Education Institute, Inc. [www.X-Plain.com]
Last reviewed: 3/6/2008
We each have about 120,000 hairs on our scalp; blonde-haired people seem to have
more than brown-haired and redheaded people.
Our entire body is covered with hair except for our lips, palms of the hands and soles
of the feet. Hair that is very thin and hard to see is called vellus. An average person
has about 5 MILLION hairs on his or her body!
Hair grows from the papilla in different phases.
Depending on where it is on the