What Is Hair?

Hair is composed of a hardened protein called keratin. There are three layers to hair:

• Cuticle - external layer of hair formed from hardened cells. It is scaly in nature and gives hair texture.
• Cortex - Under the scalp and related to hair volume. The cells of the cortex contain keratin and melanin (pigment).
• Medulla - Innermost center of hair, which is about 10% of volume, except in thin hair when the medulla may be absent.
• Root - the living part of the hair anchored in the scalp. At the end of the root is the bulb, a thicker whitish structure.
• Papilla - Empty area at the base of the bulb connecting the hair to the head. This is where the blood vessels and nerves give the hair its nourishment.

Everyone has approximately 100,000 hairs, and hair cycles every 2 to 6 years (average is 3 years) and is genetically programmed.

There are three phases of hair growth:

• Anagen Phase - the initial growth phase of hair, usually lasting about 1000 days. It regularly occurs in most of the hairs on the human head. Approximately 85% of the hair on your head grows one inch per month. During this phase, hair is very sensitive to nutrition and environment.
• Catagen Phase - Is a period of arrest which causes the follicle (root) to form a club hair and fall out. Most hair regrows because the follicle remains. As new hair grows from the root inside the follicle, it pushes out the old hair.
• Telogen Phase - Is a resting mode 3 to 4 months prior to the anagen phase starting all over again. This phase usually lasts 100 days. Approximately 10 to 15% of all hairs are in this state of rest at anygiven time.