Both men and women tend to lose hair thickness and amount as they age. This type of baldness is not usually caused by a disease. It is related to aging, heredity, and changes in the hormone testosterone. Inherited, or pattern baldness, affects many more men than women. Those with inherited hair loss show signs of hair loss before age 40. About half of all men show signs of hair loss by age 50.
Physical or Emotional Stress
Physical or emotional stress may cause one-half to three-quarters of scalp hair to shed. This kind of hair loss is called Telogen effluvium. Hair tends to come out in handfuls while you shampoo, comb, or run your hands through your hair. You may not notice this for weeks to months after the episode of stress. Hair shedding decreases over 6 to 8 months. Telogen effluvium is usually temporary. But it can become long-term (chronic).
Causes of this type of hair loss are:
- High fever or severe infection
- Major surgery, major illness, sudden blood loss
- Severe emotional stress
- Crash diets, especially those that do not contain enough protein
- Medications, including retinoids, birth control pills, beta-blockers, calcium channel blockers, certain antidepressants, NSAIDs (including ibuprofen).
Some women ages 30 to 60 may notice a thinning of the hair that affects the entire scalp. The hair loss may be heavier at first, and then gradually slow or stop. There is no known cause for this type of telogen effluvium.
Other causes of hair loss, especially if it is in an unusual pattern, include:
- Alopecia areata (bald patches on the scalp, beard, and, possibly, eyebrows; eyelashes may fall out).
- Autoimmune conditions such as lupus
- Certain infectious diseases such as syphilis
- Excessive shampooing and blow-drying
- Hormone changes
- Thyroid diseases
- Nervous habits such as continual hair pulling or scalp rubbing
- Radiation therapy
- Tinea capitis (ringworm of the scalp)
- Tumor of the ovary or adrenal glands