Hair – LifeCycle

Hair follicles grow in repeated cycles. Each cycle consists of three phases and passes through the phases independent of the neighboring hair.

Anagen Phase - Growth Phase

Approximately 85% of all hair are in the growing phase at any one time. The Anagen Phase can vary from two to six years. Hair grows approximately 12-15 cm per year and any individual hair is unlikely to grow more than one meter long.

Catagen Phase - Transitional Phase

At the end of the Anagen Phase, the hair enters into a Catagen Phase which lasts about one or two weeks. During the Catagen Phase the hair follicle shrinks to about 1/6 of the normal length. The lower part is destroyed and the dermal papilla breaks away.

Telogen Phase - Resting Phase

The Telogen phase follows the Catagen phase and normally lasts about 5-6 weeks. During this time the hair does not grow but stays attached to the follicle while the dermal papilla stays in a resting phase below. Approximately 10-15 percent of all hair are in this phase at any one time.

 

At the end of the Telogen Phase the hair follicle re-enters the Anagen Phase. The dermal papilla and the base of the follicle join together again and a new hair begins to form. If the old hair has not already been shed the new hair pushes the old one out and the growth cycle starts all over again.

Content on this page requires a newer version of Adobe Flash Player.

Get Adobe Flash player