Roughly 25% of men experience some hair loss by the time they reach 25, and the percentage goes up about ten points a decade. A third or more of women will also experience some hair loss by middle age. The good news: A small army of researchers is testing revolutionary baldness-battling treatments that should be ready a few years from now. Until then, existing prescription drugs do a decent job of helping to preserve the hair you've got.

Assuming you find hair transplants as distasteful as we do, the best bet is Rogaine (minoxidil), Propecia (finasteride), or both. If you rub Rogaine (up to $45 a month) into the scalp twice a day, you have a 59% chance of stimulating some new hair growth after four months--but you've got to keep using the stuff to maintain the effects. Propecia (up to $58 a month), which comes in pill form, has been shown to stop hair loss in 83% of male patients tested between ages 18 and 41. It too must be taken forever, and it can't be taken by women of childbearing age because it causes birth defects.

Baldness is usually triggered by a combination of genetic and hormonal factors, so researchers are attacking on both fronts. Glaxo-SmithKline is testing a drug called Dutasteride that can block nearly 100% of dihydrotestosterone (DHT), a hormone byproduct that activates hair-loss genes. The drug could hit the market in two to five years. There's also stem-cell therapy, in which doctors harvest stem cells from healthy hair follicles, multiply them in a test tube, and inject them into the skin. Human testing is just getting underway. The ideal treatment would be to identify the gene-driven process that causes baldness and then neutralize it with a topical lotion or implant hair-friendly genes. If that works, the old joke--if you want to save your hair, get a box--may finally be obsolete. Also, more research is being done into herbal hair loss remedies.

By Alex Taylor III, Associates Paola Hjelt and Lisa Munoz, Time Magazine, 2002

Alopecia or hair loss is a distressing turn of events. The scalp is often afflicted but it can occur on any part of the body.

Why does this happen? Are there different types of hair loss?

Our hair follicles perpetually cycle through a growth and resting phase. The growth phase is called anagen, the resting phase, telogen, and the time in between as the follicle shuts down for a rest, catagen.

Alopecia occurs through a disruption of either the follicle's normal cycle or by damage to the follicle itself. The evaluation of hair loss always begins with a complete medical history and physical exam.

You can assist your doctor by noting the duration and pattern of the hair loss. Are the hairs broken or shed at the roots? Has the hair loss increased recently? Do you have a family history of alopecia?

The "pull test" defines normal shedding of the hair. Grasp about 60 hairs between the thumb and index and middle fingers. Pull them gently, but hold them firmly. Six or fewer hairs left between your fingers is considered normal shedding.

The most common type of hair loss in men and women is androgenic alopecia. Each hair follicle has androgen (male hormone) receptors. Activation of these receptors by the hormone dihydrotestosterone (DHT) shortens the anagen phase. The hair follicles will shrink. With each cycle the hair becomes thinner and the follicle smaller. In women, the thinning and hair loss occurs over the entire scalp but is most pronounced at the crown of the head and areas toward the forehead.

Women with androgenic alopecia do not have greater levels of androgens. Indeed, most have normal menstrual cycles, fertility and hormonal function. What has been found is that these women have greater levels of an enzyme that converts their normal levels of testosterone into DHT, lower levels of an enzyme that converts testosterone into estrogen and more androgen receptors in the hair follicle itself. All these factors add up to more hair loss.

The medication recommended to treat androgenic alopecia in women is minoxidil (Rogaine). It works by increasing the anagen phase, activates follicles stuck in the catagen phase and enlarges the hair follicles.

One clinical trial demonstrated minimal hair regrowth in 50 per cent of women and moderate regrowth in 13 per cent. Other trials demonstrated improved hair regrowth.

Alopecia areata can appear as the sudden appearance of one- to two-centimetre-round shiny bald patches on the scalp. It occurs in two per cent of the population, equally affecting males and females. It is more common in children and young adults. The body's immune system attacks the hair follicles for unknown reasons. Some people can experience complete loss of scalp hair.

Some people with thyroid disease, eczema or vitiligo (loss of skin pigmentation) will exhibit this condition but most afflicted people are healthy.

Treatment options include local steroid injections into the bald spot, steroid creams, anthralin and minoxidil. Unfortunately, they are not completely effective. Other treatment options include several herbal hair loss remedies. However, the condition will spontaneously resolve and recur.

Emotional and physical stressors can cause sudden non- permanent hair loss called telogen effluvium. Women will notice a lot more hair on their hairbrush or shower floor. Some will experience hair loss after pregnancy or from certain medications.

Telogen effluvium occurs when a great number of hair follicles become inactivated or enter the telogen phase. The follicles will enter anagen phase one to two months after the end of the stressful event.

Traumatic alopecia is due to certain hair styling practices. Tight braiding and repeatedly twisting and tugging the hair can cause the hair to fall out.

Hair loss does not occur with frequent shampooing and conditioning. Having your hair styled, coloured, teased, sprayed or permed will not worsen hair loss.

If you suspect hair loss, consult your doctor sooner rather than later.

By Dr. Barry Dworkin, Ottawa Citizen, 04-06-2004

Alopecia, or hair loss, is a distressing turn of events. The scalp is often afflicted but it can occur on any part of the body.

Why does this happen? Are there different types of hair loss?

Our hair follicles perpetually cycle through a growth and resting phase. The growth phase is called anagen, the resting phase, telogen, and the time in between as the follicle shuts down for a rest, catagen.

Alopecia occurs through a disruption of either the follicle's normal cycle or by damage to the follicle itself. The evaluation of hair loss always begins with a complete medical history and physical exam.

You can assist your doctor by noting the duration and pattern of the hair loss. Are the hairs broken or shed at the roots? Has the hair loss increased recently? Do you have a family history of alopecia?

The "pull test" defines normal shedding of the hair. Grasp about 60 hairs between the thumb and index and middle fingers. Pull them gently, but hold them firmly. Six or fewer hairs left between your fingers is considered normal shedding.

The most common type of hair loss in men and women is androgenic alopecia. Each hair follicle has androgen (male hormone) receptors. Activation of these receptors by the hormone dihydrotestosterone (DHT) shortens the anagen phase. The hair follicles will shrink. With each cycle the hair becomes thinner and the follicle smaller. In women, the thinning and hair loss occurs over the entire scalp but is most pronounced at the crown of the head and areas toward the forehead.

Women with androgenic alopecia do not have greater levels of androgens. Indeed, most have normal menstrual cycles, fertility and hormonal function. What has been found is that these women have greater levels of an enzyme that converts their normal levels of testosterone into DHT, lower levels of an enzyme that converts testosterone into estrogen and more androgen receptors in the hair follicle itself. All these factors add up to more hair loss.

The medication recommended to treat androgenic alopecia in women is minoxidil (Rogaine). It works by increasing the anagen phase, activates follicles stuck in the catagen phase and enlarges the hair follicles.

One clinical trial demonstrated minimal hair regrowth in 50 per cent of women and moderate regrowth in 13 per cent. Other trials demonstrated improved hair regrowth.

Alopecia areata can appear as the sudden appearance of one- to two-centimetre-round shiny bald patches on the scalp. It occurs in two per cent of the population, equally affecting males and females. It is more common in children and young adults. The body's immune system attacks the hair follicles for unknown reasons. Some people can experience complete loss of scalp hair.

Some people with thyroid disease, eczema or vitiligo (loss of skin pigmentation) will exhibit this condition but most afflicted people are healthy.

Treatment options include local steroid injections into the bald spot, steroid creams, anthralin and minoxidil. Unfortunately, they are not completely effective. Other treatment options include several herbal hair loss remedies. However, the condition will spontaneously resolve and recur.

Emotional and physical stressors can cause sudden non- permanent hair loss called telogen effluvium. Women will notice a lot more hair on their hairbrush or shower floor. Some will experience hair loss after pregnancy or from certain medications.

Telogen effluvium occurs when a great number of hair follicles become inactivated or enter the telogen phase. The follicles will enter anagen phase one to two months after the end of the stressful event.

Traumatic alopecia is due to certain hair styling practices. Tight braiding and repeatedly twisting and tugging the hair can cause the hair to fall out.

Hair loss does not occur with frequent shampooing and conditioning. Having your hair styled, coloured, teased, sprayed or permed will not worsen hair loss.

If you suspect hair loss, consult your doctor sooner rather than later.

By Dr. Barry Dworkin, Ottawa Citizen, 04-06-2004