Hair Loss | Overview

 What is the normal cycle of hair growth and loss?

The normal cycle of hair growth lasts for 2 to 3 years. Each hair grows approximately 1 centimeter per month during this phase. About 90 percent of the hair on your scalp is growing at any one time. About 10 percent of the hair on your scalp, at any one time, is in a resting phase. After 3 to 4 months, the resting hair falls out and new hair starts to grow in its place.

It is normal to shed some hair each day as part of this cycle. However, some people may experience excessive (more than normal) hair loss. Hair loss of this type can affect men, women and children.

What is common baldness?

"Common baldness" usually means male-pattern baldness, or permanent-pattern baldness. It is also called androgenetic alopecia. Male-pattern baldness is the most common cause of hair loss in men. Men who have this type of hair loss usually have inherited the trait. Men who start losing their hair at an early age tend to develop more extensive baldness. In male-pattern baldness, hair loss typically results in a receding hair line and baldness on the top of the head.

Women may develop female-pattern baldness. In this form of hair loss, the hair can become thin over the entire scalp.

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Written by familydoctor.org editorial staff
Reviewed/Updated: 12/10
Created: 09/00