From Lady Godiva to the Breck Girl, Farah Fawcett to Jennifer Aniston, there
is no question that, at least for women, hair is often a defining point in
personal style. That's one reason why so many women panic
at even the thought of losing a few hairs down the drain with each shampoo.
Those fears are not unfounded, as each year more women are forced to come to
grips with the possibility of serious hair
loss. According to the American Academy of Dermatology, it's a growing
problem, affecting some 30 million women in the United States -- with some
forms of loss occurring at earlier ages, and being seen in increasing
"I have seen women as young as 15 or 16 develop hair loss problems -- it's
not common, but it's also not that rare," says Ted Daly, MD, a dermatologist
from Nassau University Medical Center on Long Island, who specializes in the
treatment of female hair loss.
But what exactly causes a woman to lose her hair? To understand that, it's
important to know a little something about how hair grows.
Experts say our tresses usually grow at the rate of about one-half inch per
month -- with each hair having a growth phase of two to six years. At that
point the hair "rests" for a period of time, then falls out -- and the follicle
from which it sprang soon starts growing a new strand. And so the cycle
continues, usually well into our senior years.
In some folks, however -- those with a genetic predisposition to hair loss
-- a group of hormones called androgens interferes with this natural process.
According to dermatologist Michael Reed, MD, androgen hormones include testosterone, androsteinedione, and dihydrotestosterone
(DHT) -- all of which are made in men's bodies in large amounts, and in women's
bodies in small amounts.
In those who are genetically susceptible, when testosterone comes in contact
with enzymes residing in the hair cell, it is converted into the more potent
androgen DHT, which then binds with receptors deep within the hair
"Over time, an excess build-up [of DHT] in the follicle causes it to begin
shrinking, which in turn alters the natural resting and growth phases of the
hair," says Reed, clinical associate professor of dermatology at NYU Medical
Center, and a specialist in female hair loss. Some of the follicles eventually
die, while others are rendered incapable of producing or maintaining healthy
hair growth. The end result, says Reed, is hair loss -- and a condition that is
medically known as androgenic alopecia.
For many decades, doctors believed that androgenic alopecia was the primary
cause of balding in both men and women. Today they know this is not true -- at
least where women are concerned.