I’m 24 and I have gray hair! What’s going on?

I was only 18 when I spotted my first gray hairs, interlopers among my chestnut-colored tresses. As a freshman in college, I chalked these gray hairs up to stress from calculus class and a bad boyfriend. But by the time I aced calculus and dumped the boyfriend, those silver wisps were still there—and now, at the age of 25, a few gray strands have multiplied to what seems like nearly a hundred, silently taunting me when I look in the mirror as if to say, “You’re getting old. You’re getting old. You’re getting old.”

To explain the mystery of graying hair, you must get to the root of the problem, err, I mean the root of your hair. Under the scalp, a tube of tissue called the hair follicle surrounds the root of every hair strand. Each follicle contains a number of pigment cells that produce melanin, the polymer that gives the growing shaft of hair its color. Usually these pigment cells continuously produce melanin, but if your body stops generating it, the strand of hair will have very little pigment to paint over it’s normally transparent hue; this base-transparency will then present itself as gray, white, or silver.

Melanin production is brought to a halt for a variety of reasons–some natural, some indicators of greater health issues. As people continue to get older, the number of pigment cells around to produce melanin will actually be reduced. Eventually, these cells will be so depleted, the hair will look completely gray. Incidentally, melanin also provides moisture to the hair strand, so when less is produced, hair tends to grow brittle, losing its bounce. This is why as your hair leans towards the color of the snowy peaks of the Alps, its texture becomes dryer and coarser, making it more curly or wiry.

My gray hair started when I was still in my teens—a far cry from the usual graying age range of 30 to 50. But it turns out that people can get gray hair at any age, depending on genetics. This means that most of us will start having gray hairs around the same age that our parents or grandparents first did. I called my mother to find out our family’s graying hairstory. She told me it wasn’t any surprise that I had started to gray at a young age—her uncle’s hair was completely white by the time he was 25. Aha! I thought. Now this mystery is starting to make sense.

Researchers have shown that gender plays a role in graying. The average male starts to gray around age 30, while women typically began to notice lighter strands around age 35. In some families, many members develop white hair in their 20s. “It obviously clusters in families in one sense. Whether that is a single gene or common gene we don’t know,” writes Dr. Meyer in the magazine Scientific American. “Generally speaking, among Caucasians, 50% are 50% gray by age 50. There is, however, wide variation. This number differs for other ethnic groups, again demonstrating the effect of genetics.” But this biological fact of life varies greatly from person to person, which made dermatologists and geneticists conclude that age is not the the only indicator of when gray hair will appear.

For starters, smoking is known to decrease melanin production. Sometimes, the arrival of gray hair can be a sign of an underlying health problem. Werner’s syndrome, a disease that mirrors the symptoms of aging in people as young as 20, can spur the premature growth of gray hair. Pernicious anemia, a disease marked by a vitamin B12 deficiency, is also associated with decreased melanin production.

Although there are people who think that a big shock or trauma can turn a person’s hair white overnight, only a rare disease has been known to cause this phenomenon. Called alopecia areata, the condition causes the thicker, darker hairs to stop growing before it affects the growth of gray hairs—meaning people with the disease seem to “go gray” overnight as the darker strands are diminished and the gray ones keep on growing strong.

Overnight graying myth aside, what about that pesky old wive’s tale that says pulling out a gray will result in five more springing in it’s place? That’s also wrong! So yank away. I, however, don’t have that kind of patience, so it’s back to the salon for me, for a little color to cover those stubborn grays.