Hair loss is a major problem in our society due to the fact that it has a great deal of social and cultural importance. Normal hair loss is approximately 100 hairs per day; the average scalp contains about 100,000 hairs. Each individual hair grows about a half inch per month, survives for approximately 4.5 years, and is replaced within 6 months. Genetic hair loss is the body’s inability to produce new hair rather than loss of hair. There are many different reasons that cause hair loss and most of them can be avoided or treated with success.
The most common type of hair loss is called androgenic alopecia. Androgenic alopecia is a hereditary form of hair loss that can be seen in both males and females. It is more common in men then women; about 25% of men begin to bald by the time they are 30 and two thirds are bald by the time they are 60 years old. Androgenic alopecia in males is characterized by hair loss that begins in the temples and crown. Female hair loss is limited to thinning at the front, the sides of the head and the crown.
Alopecia areata is an auto-immune disease of unknown cause. It can occur during childhood or any age. Alopecia areata is characterized by a patchy hair loss that usually grows back on its own. Thyroid disorders, both hyperthyroidism and hypothyroidism may cause this pattern of hair loss. Proper treatment of thyroid disease can reverse the hair loss. Medications can also cause hair loss. Certain hair styles that pull on the hair (braids, ponytails) and hair treatments can cause hair loss.
Poor nutrition such as low protein intake associated with certain diets or iron deficiency may cause hair loss. Iron deficiency can also be seen in females with heavy menstrual cycles. Chemotherapy or radiation therapy may cause hair loss, but hair re-growth occurs after cessation of treatment. Recent illness or surgery can cause hair loss, as well as childbirth (telogen effluvium). During pregnancy hair growth increases, however after delivery hair loss may occur and last up to 6 months.
Fungus infections of the scalp, also known as ringworm can cause hair loss. This type of infection is contagious and most commonly occurs in children. Siblings may need to be checked for any scalp infections.
Psychological disorder such as trichotillomania may also present with hair loss. Trichotillomania is a disorder in which the individual pulls their own hair. Although most commonly seen in children, trichotillomania can also be seen in adults.
People who experience hair loss should see their doctor as soon as possible. Genetic hair loss will have a better success rate of prevention the sooner it is treated. Other causes of hair loss can also be investigated by laboratory screening and can be reversed by appropriate treatment.
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