Q. What causes hair to turn gray? Why do some people go gray at a young age? Is there any evidence that rapid weight loss, slow weight loss or intense exercise accelerates graying? I’ve noticed that women in dieting “after” pictures commonly have a new hair color, while older male marathon runners are more gray and haggard than average.
A. Hair goes gray as cells called melanocytes at the base of each hair follicle get damaged by disease, environmental exposures or age.
Everyone has some gray hairs throughout life, but the balance tends to tip in the 40s or 50s, with the rate of change varying by genetics, gender and ethnicity, said Dr. James Kirkland, director of the Robert and Arlene Kogod Center on Aging at the Mayo Clinic. Blacks tend to go gray later than Caucasians, with Asians falling somewhere in between. Women generally gray later than men.
Smoking can also accelerate color change, and early graying could be a sign of autoimmune, thyroid or heart disease. “If you’ve got heart disease and your hair is gray, it’s a sign of worse heart disease,” Dr. Kirkland said.
Some people held in concentration camps during World War II who were deprived of proper nutrition also went prematurely gray, said Dr. Wilma Bergfeld, a dermatologist at the Cleveland Clinic, who specializes in hair disorders. “Everything is determined by the health of the pigment-producing cell,” she said.
Dr. Bergfeld said she doesn’t know of anyone who has gone gray because of weight loss or exercise. Most activities that are damaging to the hair, like rapidly losing more than 20 pounds or getting chemotherapy treatment, will cause hair loss rather than a change of color, she said.
Unfortunately, there are no medications approved to restore hair color, though in early testing of the anti-hair-loss drug minoxidil, Dr. Bergfeld said that she and other researchers noticed the drug sometimes also restored hair color, suggesting it was rejuvenating the melanocytes.