Stress Really Does Make Hair Go Gray Faster


There is some truth to the longstanding anecdote that your locks can lose color when you’re stressed.

A team of researchers has found that in mice, stressful events trigger damage the stem cells that are responsible for producing pigment in hair. These stem cells, found near the base of each hair follicle, differentiate to form more specialized cells called melanocytes, which generate the brown, black, red and yellow hues in hair and skin. Stress makes the stem cells differentiate faster, exhausting their number and resulting in strands that are more likely to be transparent — gray.

The study, published Wednesday in Nature, also found that the sympathetic nervous system, which prepares the body to respond to threats, plays an important role in the graying process.

“Normally, the sympathetic nervous system is an emergency system for fight or flight, and it is supposed to be very beneficial or, at the very least, it’s effects are supposed to be transient and reversible,” said Ya-Chieh Hsu, a stem cell biologist at Harvard University who led the study.

The researchers found that the sympathetic nerve cells released a neurotransmitter called noradrenaline that was taken up by nearby melanocyte stem cells. Then a series of events unfolded in quick succession: The melanocyte stem cells proliferated and turned into specialized pigment-producing cells, which abandoned their niche near the base of the follicle and left the hair without a source of pigmentation.

“I was amazed by how dramatic this change is,” said Mayumi Ito, a biologist at the New York University School of Medicine who was not involved in the study. In her own research on aging mice, the graying process was gradual: The depletion of melanocyte stem cells led first to a few salt and pepper strands and then to gray or white fur, much as humans begin to see more white hair as they get older. But in Dr. Hsu’s study, acute stress depleted the entire melanocyte stem cell population in mice in just five days.

Her team also found that the graying process could be halted with drugs known as CDK inhibitors, which stop the proliferation of stem cells, or by blocking the release of noradrenaline.

The findings underscore the consequences of triggering a survival mechanism when the situation isn’t life-threatening.

“Stress is a normal part of life, but there are situations where stress is helpful and situations where it is detrimental,” said Subroto Chatterjee, a biologist at Johns Hopkins University who studies the effects of stress on the cells in blood vessels.

Other studies have shown that stress is just one factor affecting how quickly hair goes gray, Dr. Chatterjee said. Genes and diet play a big role as well.



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