Hair loss in men can be devastating to self-esteem, confidence, and body image. Consequently, hair replacement is a huge industry. But, hair loss can also be a sign of more serious medical problems.

Marc Connelly, playwright and author of Green Pastures, was almost totally bald. One afternoon at the Round Table in the Algonquin dining room in New York City, a friend walked up and ran his hand over the playwright's bare pate and said, "That feels just like my wife's bottom." Connelly stroked his head thoughtfully and replied, "Why, so it does!"

However, most men are not so glib about their bald heads. Significant baldness strikes about 40% of men by their mid-thirties. By age 75, more than 65% of men have the characteristic monk hairline—bald on top with hair only around the temples and back of head. Additionally, about 25% of the estimated 40 million bald American men pony up big time—about $550 million yearly—for the traditional hair replacement therapies: "rugs, plugs, and drugs."

"Men fear baldness so much because it's a sign of the aging process—that he's getting older and becoming more vulnerable," says William Boss, MD, associate chief of plastic surgery at Hackensack Medical Center. "It's natural for males to think they are invincible, but baldness is a very visible chink in the armor."

Oddly, a completely shaven head—like that of Mr. Clean, Yul Brenner as the King of Siam, and Sean Connery—can be the picture of manly virility. For most men, the dreaded loss of hair starts with a receding hairline and, with time, results in hair that covers only the back of the neck and just over the ears. If balding starts in the teen years, it is usually extensive. Some balding men only call attention to their condition by growing the hair above their ears very long and then combing the scant strands across their glistening domes. Others just wear hairpieces.

Predicting Baldness Patterns

"Look to your father and grandfather to get an idea of what your own hair line may do as you age," says Mark Stevens, PhD, professor of psychology at the University of Southern California. Actually, the most dominant part of your DNA inheritance comes from your mother. So look closely at her brothers and her father for clues about your hairline."

However, hair loss can be more than fading confidence or spotting many bald relatives perched on the branches of your family tree. Thomas F. Downham II, MD, in the department of dermatology at Henry Ford Medical Center in Detroit, Michigan, points out, "Don't just jump to the conclusion you have male pattern baldness because you are losing some hair. That hair loss could also be a sign of low serum iron, an early indication of a blood condition. Or it could be caused by the medications you are taking, or it could be a sign hypothyroidism. Of the medical specialists, dermatologists are best suited to evaluate hair loss." Moreover, hair is very sensitive to antihypertensive drugs, beta blockers, and anticancer preparations.

Historically, there have been many theories about the causes of hair loss. Aristotle thought sexual indulgence caused male pattern baldness. Genetics notwithstanding, you could go bald in the 1940s and 1950s from wearing a hat every day—or so people thought. Various other theories implicated scalp tension as the cause of hair loss. Following that was a theory that the scalp muscles led to a shearing stress in the skin. The most recent explanation for male baldness has held sway for three decades. It's a tongue-twisting condition known as androgenetic alopecia.

Doctors think a male hormone, androgen, interrupts the natural growth cycle of hair in the front and crown regions of the scalp. But it doesn't happen without genetic predisposition. You can also lose a lot of hair during times of intense stress. Being shipped off to a war, losing a job, being hospitalized, or the rigors of divorce court can cause a type of balding known as diffuse hair loss. If the stress continues unabated, hair loss will become patchy and, often, permanent.

Pros and Cons of Hair Transplants

For reasons doctors don't fully understand, the hair at the back of the head is genetically hardier. And that observation led to a major industry—hair transplanting. Doctors remove a patch of hair-bearing skin from the back of the head and sew the scalp shut. Using either a scalpel or a laser, practitioners make holes for the grafts in the scalp and then plunk in micrografts, containing one or two hairs, or minigrafts—plugs of skin with three or four hairs.

"Transplanted hair is very soft and downy and not like the hair you had before," cautions Dr. Downham. "I would say that about 50%-60% of my patients have had a good response from transplanting. However, if you have a lot of bare skin on your head, you won't get any significant amount of transplanted hair to grow over the long run. You may require additional transplants later on in life."

There are no reliable scientific data yet on the long-term survival of transplanted hair. Depending on the procedure, it can take six months to a year for a natural appearance to show. Cost? Better bring all your credit cards. Hair transplants can range from $3,000 to $10,000 depending on the number of procedures involved. One session can require two to five hours.

Hair Growth Treatments: Do They Work?

About 30% of men participating in clinical trials have had success with an anti-high blood pressure medication, minoxidil, which was first used for hair growth in 1980. Since then, a 2% preparation has been approved for over-the-counter (OTC) distribution, marketed as Rogaine. Minoxidil is rubbed into the scalp and probably helps by increasing blood circulation there. The FDA is currently considering approving a 5% minoxidil solution for OTC use, as well.

Another medicine being studied as a treatment for baldness is finasteride, taken as a one milligram tablet. The drug works by reducing the hormone which interferes with hair growth. In clinical trials at two large medical centers, 1,500 men took the drug, and researchers found that the majority of subjects enjoyed significantly increased hair growth.

Of course, if a bald head makes no difference at all to your self-esteem, you can always join forces with the 10,000 proud members of the Bald Headed Men of America. Their mission? To convince you that skin is in.