The idea that along with aging chronic stress is a primary cause of our hair turning gray is accepted as conventional wisdom. We watch as presidents — most recently Barack Obama — gradually turn gray during their time in office and joke that stressful situations accelerate our graying process. But is there an actual medical reason why this happens, or is it simply one of the most visible parts of the aging process, and what we happen to notice first?
Though the science jury has been out on this particular question in the past, a new study offers some new insight into whether stress — or chronic illness — is responsible for those pesky gray (or white) hairs you constantly find yourself plucking in the bathroom mirror.
Published in the journal PLOS Biology, the research — conducted at the National Institutes of Health and the University of Alabama, Birmingham — found a direct connection between the genes that control hair color and those that tell our bodies of an infection or illness.
Even though this connection seems like common sense to us, the finding was initially surprising to Dr. Melissa Harris, the primary author and assistant professor in the Department of Biology at UAB. “Genomic tools allow us to assess how all of the genes within our genome change their expression under different conditions, and sometimes they change in ways that we don’t anticipate,” she said in a statement. “We are interested in genes that affect how our stem cells are maintained over time. We like to study gray hair because it’s an easy read-out of melanocyte stem cell dysfunction.”
These melanocyte stem cells produce the materials that are responsible for making and depositing pigment into the hair shaft. On research conducted on mice, when innate immune signaling was artificially activated on subject predisposed for getting gray hair, they ended up producing even more gray hair.
“This new discovery suggests that genes that control pigment in hair and skin also work to control the innate immune system,” William Pavan, study coauthor and chief of the Genetic Disease Research Branch at the National Health Institute’s National Human Genome Research Institute said in a statement. “These results may enhance our understanding of hair graying. More importantly, discovering this connection will help us understand pigmentation diseases with innate immune system involvement like vitiligo.” (Vitiligo is a skin discoloration condition where patches of skin are different colors. It affects between 0.5 percent to 1 percent of all humans.)
Of course, it’s important to remember that this research has only been conducted on mice (so far) and still is in early stages, but is an interesting addition to what we know about the graying process.