Gray Matters

With time and age comes wisdom, right? It certainly is a comforting thought as we grow older, since the acuity of some faculties dwindles noticeably. One visually obvious sign of aging for most of us is the graying of hair. I have always taken it for granted that this change would occur in my own appearance, but without much thought to the process. Perhaps, because this is the year I turn 50; or perhaps because I’m feeling particularly wise this week, I wanted to discuss the graying of hair. . .how and why it happens.

Actually, the ‘natural’ or base color of our hair is either gray or white. Melanin pigment is produced in the hair bulbs to generate a color over this basic tint. As a person ages, the pigment cells deteriorate and produce less and less melanin. As a result, the overlying hair color fades, and the underlying gray or white progressively shows through. Generally, the graying of hair begins around the age of 30 for men and 35 for women. But, the onset varies greatly between individuals–with heredity and environmental exposures being the chief factors in this variability. Also, for unclear reasons, the graying of hair is generally occurring at younger ages in all Americans. Causal possibilities include changes in diet, changes in lifestyle, and deterioration of our environment. Of course, whether this trend will continue is unknown.

Hair color is determined by melanin pigment distributed through the middle of the hair shaft. The range of color–from blond to brown to black is determined by the size, and obviously, the color of the pigment granules. Darker hair shows higher trace amounts of copper. The latter observation supports the fact that metal-based melanin molecules are more highly developed in dark-haired people. Along these lines, it has been speculated that copper deficiency may be a factor in some folks’ graying of hair, but empiric testing doesn’t exist to support this notion. You’re “dyeing” to know more. . .so read on.

For unclear reasons, the melanocytes (cells which manufacture melanin) can slow down or stop completely. As this process continues, the hair color turns first yellow–then gray or white. Air bubbles may also work their way into the hair shaft and contribute to graying by blocking the passage of melanin in specific hairs. Obviously, there is a genetic connection with how hair ages. . .but this is a gray area, indeed! Though we all know whole families you all seem to have gray hair by their late 20s or early 30s, a strong genetic predisposition for this phenomenon is not easy to identify. But, it is clear that the graying of hair follows the same general process for both light and dark-haired individuals. . .though the pigment loss is, of course, more obvious in darker-haired individuals.

Although certain specific medical conditions: vitiligo, albinism, pernicious anemia, and thyroid problems can lead to dilution of hair pigment (creating gray or white hair), stress does not cause gray hair. Along those lines, you’ve heard about the little girl who while watching her mother cook asked, “Mom, why are some of your hairs white?” Seizing the opportunity, the Mother responded, ” Well, every time you do something wrong, make me unhappy, or make me cry, one of my hairs turns white.” Astutely, the little girl queried, “So, Momma, why are ALL of grandma’s hairs white?”

Because the hair shaft is made of dead cells, its color cannot be changed except through color treatment of some kind. Once graying has begun, certain amounts of dark hair remain in a resting phase while the new hair is both gray and growing. Under normal circumstances, the remaining dark hair is eventually shed, leaving only the gray hair. The loss of the dark hair can be accelerated by an acutely stressful event such as an accident, surgery, or death of a loved one. Such dramatic, sudden hair loss is called “diffuse alopecia areata”. And since it seems to preferentially affect pigmented hairs, a person under great duress truly can ‘become gray almost overnight.’ Having combed through a number of facts, I’ve a little more to tell you lest I cut you short this week.

Since most of us have hundreds of thousands of hairs on our heads, the graying process usually takes 10–20 years from start to finish. And, though stress and worry cannot cause hair that is not meant to gray to do so, it may in fact serve to speed up the overall process. Truly, doesn’t it appear that many of our Presidents seem to have grayed rapidly during their terms in office? Such an observation may be more than anecdotal. . .especially when one considers how harried our Chief Executives’ jobs can be!

There actually is research in progress aimed at altering the gene which programs the cessation of melanin production. We do know that aging doesn’t destroy the hair’s ability to produce pigment, it simply turns it off. So, the research is concentrating on finding a way to switch the pigment production center(s) back on.

If, in fact, the above treatment is discovered, we may gradually lose that characteristic that we now so fondly associate with wisdom, experience, and longitudinal perspective. I’m not sure about you, but I’m willing to forfeit the mark of distinguished maturity whenever this scientific breakthrough occurs. And, in the meantime, as I ponder my own aging, I truly agree with Collette when she commented a decade later in her own life, “You must not pity me because my sixtieth year finds me still astonished. To be astonished is one of the surest ways of not growing old too quickly.”

Stephen L. Hines, M.D.
January 2001