Hair Loss Health Center

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Hair Loss

Hair Loss Overview

More than half of men and women in the United States experience hair loss. About 30% of people have hair loss by age 30 years, and about 50% have hair loss by age 50 years. Hair loss is so common that most of the time it is considered a normal variation and not a disease. Other animals closely related to humans, such as the chimpanzee, also lose their hair.

Forms of hair loss
- Androgenic alopecia - The most common type of hair loss, also called male pattern baldness
- Traumatic alopecia - Hair loss from hair being torn out
- Drug-induced alopecia - Hair loss caused by one of many medications
- Alopecia areata - Patchy, usually reversible, hair loss
Hair loss varies widely with race.
- Japanese men develop baldness less commonly than whites do. On average they also develop balding about 10 years later.
- Blacks are 4 times less likely to have abnormal hair loss than are whites.
Women develop hair loss as frequently as men do, but because of hormonal differences women don’t lose as much hair volume.
- Differences in hair styling allow women to hide hair loss more effectively than men.
- A woman may not notice hair loss itself but may notice that her ponytail or braid is getting thinner.
- Women also have a different pattern of balding than men.
Hair loss has few medical complications, but several serious conditions can cause it. In addition, there are some psychological effects associated with going bald. People with hair loss may sometimes be more likely to have a negative body image than those without hair loss.
There are 3 cycles of hair growth–growing, resting, and shedding.
- In most animals these cycles change with the season, and all hairs are in the same part of the cycle at the same time. This is why animals grow a thicker coat in the fall and shed most in the spring.
- Unlike most animals, in humans each hair has its own pattern of growing, resting, and shedding.
  - Each person sheds hair and regrows hair every day.
  - When this balance is disturbed and more hairs are shed than are regrown, alopecia or hair loss results.

Hair Loss Causes

Common causes of hair loss
- Male pattern baldness
- Trauma
- Chemicals
- Medications such as allopurinol (Zyloprim) and warfarin (Coumadin)
- Poor nutrition
- Stress, for example, during a major illness
Uncommon causes of alopecia
- Poor blood flow
- Infections such as syphilis
- Skin diseases such as lupus
- Cancers
- Hormone problems
- Kidney failure
- Liver failure

Hair Loss Symptoms

Most people notice hair loss when looking at themselves in a mirror.
You may also find many hairs on your pillow in the morning or in your hairbrush or comb.
A woman may notice a decrease in the size of her ponytail.
Aside from the thinning hair itself, most people do not have other problems associated with hair loss.