Several years ago, Sara Taggart started noticing she was losing a lot of hair whenever she took a shower. As she combed it, more hairs would end up in the sink. Then one day she noticed a patch of bare skin on the back of her head - a bald spot.
Taggart, who manages a private estate in Baltimore County, was distraught. Her mother had lost a lot of her hair in her 60s and 70s, gradually becoming bald. But Taggart was only 53.
"I was afraid this was going to happen to me, too," she says. "My family started noticing I was losing my hair. Then my friends said, 'Oh my goodness, you're losing a lot of hair.' It was making me so uncomfortable and depressed, I started shopping for a wig. Then I said 'No! I've got to go for help.' "
After examining her thoroughly to rule out any medical reason for hair loss, dermatologist Robert Weiss prescribed spironolactone. A diuretic commonly used for high blood pressure, spironolactone also blocks androgens, male hormones that can accelerate hair loss.
Taggart's hair has grown back healthy and thick, but she remembers the scare.
Although most attention has focused on men who lose their hair, hair thinning and shedding is common in women and can be more devastating, dermatologists say.
For reasons ranging from chemotherapy to the hormones of pregnancy, millions of American women experience the shock of temporary hair loss. But some have genetic hair loss because of the same hormonal process that causes men to bald. The American Academy of Dermatology says there are no statistics available on exactly how many.
Genetically based hair thinning, known as androgenetic alopecia, can be tougher psychologically on women than on men, says dermatologist Margaret Weiss, an assistant professor of dermatology at Johns Hopkins Medical Institutions who operates a private practice in Baltimore County with her husband, Robert.
"Hair loss doesn't have to be as severe in a woman as it is in a man for her to feel [unattractive]," says Margaret Weiss. "A guy can have just enough hair to frame his face and look fine - but for a woman, the same amount of hair would not look fine.
"Psychologically, hair loss is very difficult for women because society is so much less accepting of their physical imperfections. There are no bald role models for women as there are for men. And even though it is very tough on men to have their hair thin, they've seen their fathers going through it."
Composed from a form of protein also found in fingernails and toenails, hair depends upon a diet that contains adequate protein. Each hair shaft is rooted in a minute tube of skin called a follicle, which operates on a fairly predictable schedule of growing and resting. Normally, a growing phase will last several years followed by a resting phase of several months. Then new hair begins to grow and the old hair falls out.
It is normal to lose 50 to 100 hairs a day. Blonds have the most hair - about 140,000 hairs - followed by brunettes - 105,000 - and redheads - 90,000. Hair grows about a half-inch each month; but as people age, the rate can slow.
The normal adult hairline is in the shape of an M, differing from the juvenile straight-across hairline. In men with genetic pattern baldness, the hairline can recede to resemble a W, but women with genetically thinning hair usually maintain their hairline while the hair thins on the top of their heads.
Androgenetic alopecia occurs when a person possesses an excess amount of an enzyme that converts the testosterone in their follicles into another male hormone, dehydrotestosterone, or DHT. DHT causes follicles on the scalp to shrink and grow hairs that are finer, shorter and less pigmented. Eventually the follicles stop hair production.
This condition can be inherited from either side of the family. Like men, women with androgenetic alopecia can begin losing their hair in their teens, 20s or 30s. Though they never become bald the way men do - they don't have as much testosterone to create DHT - some women will see a male pattern hair loss of an enlarging bare patch at the top of the head. Many more women will get diffuse hair loss all over the head.
Dermatologist Lynn Drake, president of the American Academy of Dermatology and chairwoman of the department of dermatology at University of Oklahoma Health Sciences Center, believes many women who are told they have genetic pattern baldness are mistakenly diagnosed.
"There are over 290 drugs - such as beta blockers or lithium - that have been associated with hair loss in women," she says. "If you stop or change the drug, the hair loss stops too."
Many other underlying causes, such as thyroid disease and a type of anemia that is not revealed by the usual blood test, can cause hair loss. Drake has also observed that some vegetarians who don't get enough protein and certain long-distance runners - those who also have problems ovulating due to low body fat - lose scalp hair.