Is our history written in our hair?

Recent research into the cause of prematurely graying hair strands is offering a faint hope for two promising outcomes: reversal of unwelcome sudden graying and possible access to our biological history hidden compressed in minute hair segments—not unlike the rings in a tree trunk holding information about the life of a tree. 

Researchers have found evidence that stress may indeed be a cause of early graying, and that in some cases a reversal of graying can occur with a decrease in stress. 

Hair color is determined by melanin pigments produced in melanocytes, which in turn are produced by stem cells living in the hair follicles at the base of hair strands. Norepinephrine secretions affect the melanocyte stem cells during stress-related overactivity of the sympathetic nervous system. Without these stem cells, new hair strands remain gray or white. Unfortunately, there is no known method to turn stem cells back on, but it may be possible to interrupt the stress with accepted stress-reduction methods. The mathematical models suggest that if a certain minimum of stem cells remained, the strands may revert to their original color as the stressful event ends.

Hair growth takes place under the skin in hair follicles. Hundreds upon hundreds of protein molecules are laid down in the growing hair shaft. Cells in the follicles pick up various hormonal signals, which change some of these proteins. As the hair grows out of the scalp it hardens, preserving the protein molecules into stable colored microscopic stripes. Subtle variations in color have been detected in normal hair strands under high-resolution scanners. These colored microscopic stripes represent changes in hundreds or thousands of proteins. These changes serve as records of what goes on in the chemistry of the rest of the body. 

So, the first message from all this hair-splitting research is that the day is near when we may be able to restore some stress-related gray strands to their original color without going to the hair salon. The second message is that studying hair color changes may be an avenue to recalling biological messages of health history. 
—George Szasz, CM, MD

Additional reading

Bening S. Stress may turn hair gray, but calm may reverse it. WebMD News Brief. Accessed 27 July 2021.

eLife. Hair is a history book. Accessed 27 July 2021.

Rosenberg AM, Rausser S, Ren J, et al. Quantitative mapping of human hair greying and reversal in relation to life stress. eLife. Accessed 27 July 2021.

This post has not been peer reviewed by the BCMJ Editorial Board.

Leave a Reply