The lifecycle of hair consists of 3 phases.
- Anagen is the longest phase, in which the hair is growing. It usually last 2 to 3 years.
- Catagen or intermediate phase is the shortest phase. The lower 2/3 of the follicle is destroyed.
- Telogen is the resting or falling out phase. The follicle is preparing to return to the anagen phase.
Parts of the hair and skin are a follows:
- Papilla This is a group of specialized cells that are intertwined with capillaries. This is where a new hair develops.
- Hair Follicle This is a sophisticated receptacle in the scalp from which the hair grows. Rapid cellular activity in the bulb is responsible for providing the cells to make form the hair shaft.
- Sebaceous Gland This is an oil gland in the skin. It is hormone regulated and over production of hormones can form sebaceous 'plugs' that clog the follicles.
- Capillaries Not Shown in the picture: These are small blood vessels that carry oxygen and nutrients to the papilla as well as carry toxins away from the follicle.
- EpidermisNot labeled in the picture. This is the top layer of skin that joins the hair follicle.
- Stratum Corneum Not shown in the picture. This is the layer of dead skin cells. When you exfoliate, this the layer of skin that you remove. Excess oil and debree can build up at the opening of the hair follicle and cause the follicle to be blocked.