The most common cause of
hair loss is inherited hair loss (androgenetic
alopecia)-you inherit the tendency to go bald from either or both of your
parents. About 50% of all people have this type of hair loss by about 50 years
of age.1, 2
Hair loss may affect children as well as adults. Certain diseases,
medications, or scarring can cause hair loss. Alopecia areata, which is hair
loss caused by an
autoimmune disease, affects about
1% of the population and occurs in children and adults.3 A fungal infection called ringworm of the scalp
(tinea capitis) is very common in children and can also
cause hair loss.
Hair grows everywhere on the human skin except on the palms of our hands and the soles of our feet, but many hairs are so fine they're virtually invisible. Hair is made up of a protein called keratin that is produced in hair follicles in the outer layer of skin. As follicles produce new hair cells, old cells are being pushed out through the surface of the skin at the rate of about six inches a year. The hair you can see is actually a string of dead keratin cells. The average adult head has about...