We all remember that old uncle with the horseshoe-shaped fringe of hair encircling the back of his otherwise bare pate. Along with the spare tire, baldness has always been one of those decidedly un-cool signs of aging.

Even though bald celebrities like Bruce Willis, Michael Jordan, Patrick Stewart and American Idol’s Chris Daughtry have achieved sex symbol status, many of the estimated 40 million American men -- and women -- who are going bald aren’t content with losing their hair. They’re spending more than $1 billion a year on hair transplants, lotions, toupees, and even spray-on hair to combat baldness.


Chris Trotman/Getty Images for NASCAR
NBA star Michael Jordan

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Singer Chris Daughtry
In this article, we’ll find out which, if any, baldness treatments actually work. But first, let’s look at why people lose their hair.

What Causes Baldness?

Just underneath the skin on the head are follicles -- an estimated 100,000 of them per person. One hair grows from each of these follicles in a cycle made up of three distinct phases:

  • Anagen - Growth phase
  • Catagen - In-between phase
  • Telogen - Falling-out phase

Each hair grows at a rate of about one-half inch per month for two to six years, and then falls out. If you see hair in your brush or on your shower floor in the morning, don’t be alarmed that you’re going bald. It’s normal for people to lose 50 to 100 hairs each day as part of the normal telogen cycle. You're balding, however, when more hair falls out than is replaced, the new hair is thinner than the hair that fell out, or the hair falls out in clumps.

Video Gallery: Balding Treatments
For men who are losing their hair, it is no laughing matter. For some, it starts in their late teens and by age 50, about half of all men will be losing their hair. In 95 percent of the cases, classic male pattern hair loss is to blame. See how balding can be treated in this video from DWJTV.

One of the main causes of baldness is when the male hormone testosterone is converted to a form called dihydrotestosterone (DHT). DHT acts on the hair follicle to slow down hair production and produce thinner, weaker hairs. Eventually, hair production in the follicles stops. Women also have a small amount of testosterone, but estrogen weakens its effects until menopause, when estrogen production slows (that’s why many women find themselves facing hair loss after menopause).

No Testosterone, No Baldness
When the Greek physician Hippocrates noted that castration prevented eunuchs from going bald -- he was unknowingly remarking on the effects of testosterone. In the 1940s, Yale University anatomist James B. Hamilton studied the effects of testosterone on hair loss in a pair of twins. One of the brothers was bald. The other had been castrated in a mental institution. When Hamilton gave the castrated man shots of testosterone, his hair fell out and never grew back.