There are many causes for hair loss in men or women.
However, in the overwhelming majority of males with hair loss, the cause is
hereditary androgenetic alopecia, more commonly known as “male pattern
baldness.” The presence of the hormone, dihydrotestosterone (DHT), in a
genetically susceptible man, is necessary for this problem to occur. Similarly,
for females most patients presenting with hair loss have hereditary female
pattern hair loss. This condition is still being researched, but the hormone
influences on hereditary hair loss in females may be different from those in
Some of the less common causes of hair loss, which are
reversible with treatment, include thyroid disease, iron deficiency, high
fever, surgery or general anesthesia, “crash diets,” childbirth, and certain
medications. There are also certain dermatologic scalp disorders that can
result in temporary or permanent hair loss, such as lupus, lichen planopilaris,
and alopecia areata.
Many myths abound regarding this topic; hair loss is NOT caused by poor
circulation, clogged hair follicles, frequent shampooing, the wearing of hats
or helmets, or the presence of mites.
It is also important to remember that most adults lose
approximately 125-75 hairs
from their scalps every day due to the natural process whereby some hairs go into a dormant state (telogen), and
others come out of this state and begin to sprout a new hair (anagen). As long
as the process remains balanced, the number of hairs on the scalp remains
constant. One other minor factor in hair loss is stress, which is thought to accelerate already genetically programmed
hair loss. However, it probably does not cause hair loss by itself without the necessary genes and hormones.
The tendency for male and female pattern hair loss is genetically inherited
from either side of the family and begins to develop after puberty. Hair on the scalp that is genetically
susceptible to androgenetic alopecia (generally the front and top of the scalp), starts to shrink in
its shaft diameter and potential length during each 3 to 5 year “life cycle,”
until it eventually disappears. The hair on the back and sides of most men’s scalps is usually
genetically “permanent” hair, which is destined to remain for that man’s lifetime.
HairLoss in Men
HairLoss in Women