Stress makes your hair gray

Researchers have discovered that "genotoxic stress" does damage to DNA and reduces melanocyte stem cells within hair follicles that are responsible for making those pigment-producing cells. When confronted with a tough situation, instead of dying off, these stem cells differentiate and form fully mature melanocytes themselves.

Researchers believe that anything that can limit stress may stop the graying from happening.
Emi Nishimura of Tokyo Medical and Dental University said: "The DNA in cells is under constant attack by exogenously-and endogenously-arising DNA-damaging agents such as mutagenic chemicals, ultraviolet light and ionizing radiation. It is estimated that a single cell in mammals can encounter approximately 100,000 DNA damaging events per day."

"Once stem cells are damaged irreversibly, the damaged stem cells need to be eliminated to maintain the quality of the stem cell pools. We have found that excessive genotoxic stress triggers differentiation of melanocyte stem cells," Nishimura added.

Nishimura believes that differentiation might be a more sophisticated way to get rid of those cells rather than stimulating their death.
Findings of this research were published in the journal Cell.