The primary component of hair fiber is a kind of protein that called keratin. It also contains natural oils (lipids) and water. Hairs grow from follicles found all over the human body except on the palms of the hands and soles of the feet and on the lips. Human scalp contains about 120,000 to 200,000 hairs. Their growth starts since birth and will grow until old age. In order to understand the causes of hair loss you have to learn about 3 phases of your hair growth cycle.

The life cycle of hair has 3 stages:

Anagen or active growth phase, Catagen or transition phase and Telogen or resting phase

The anagen phase refers to the stage that hair grows continually about half an inch per month. This stage lasts 2 to 8 years. About 90% of hairs are in this stage at any time. People who can’t grow their hair long have short anagen phase and people who have an active, healthy anagen growth phase have long hair.

When the Anagen growth phase comes to an end, the next transitional phase starts.During the catagen phase, structural and chemical changes take place in the follicle and growth of the hair completely stops. This phase lasts about 2 to 3 weeks and 3% of all hairs are in this phase at any time.Then, they move to the next stage.

In the final phase of telogen hair sheds and the follicles are completely rest from producing keratin. This phase lasts about 3 months.When the cycle passes this stage, anagen starts again.

If all of our hairs were in the same phase at the same time they would all fall together!!! But instead of that they fall out at different times independent from their neighbors.

Approximately 25 to 100 hairs shed normally every day. Hair grows faster in the summer and slower in the winter. Its growth depends on age too. Younger people have more hair growth than older.