Researchers Say Stress May Actually Turn Hair Gray

We've all heard someone say that their spouse or kids are giving them gray hair. Most think that is just a joke. Stress can cause one to lose the color in their hair, and a group of scientists has discovered why that happens. The researchers say that stress activates nerves that are part of the fight-or-flight response that causes permanent damage to the pigment-regenerating stem cells in hair follicles.

The sympathetic nervous system has nerves that branch out into each hair follicle on the skin. Stress causes these nerves to release the chemical norepinephrine that gets taken up by nearby pigment-regenerating stem cells. In the hair follicles, certain stem cells are reservoirs of pigment-producing cells.

As hair regenerates, some stem cells convert into pigment-producing cells that color the hair. Norepinephrine from the nerves causes the stem cells to activate excessively, converting all stem cells into pigment-producing cells, deplete the reservoir.

The team says that once all the pigment-regenerating stem cells are lost, you can't regenerate pigments anymore, and the damage is permanent. The team started their researcher with a whole-body response and progressively zoomed in on individual organ systems, cell-to-cell interaction, and eventually, molecular dynamics. Going from the highest level to the smallest details required the team to work with many scientists around the world.

The researchers say that their findings can help to illuminate the broader effects of stress on various organs and tissues. The understandings could pave the way for new studies that seek to modify or block the damaging effects of stress. A provisional patent has been filed on the team's findings, and the team is working with commercial partners that may be interested in clinical and cosmetic applications.