Stress Can Turn Hair Into Gray, Scientists Say

Hair turning prematurely white in survivors of bomb attacks during World War II has been reported. An Australian airline pilot saw his hair go gray months after landing a plane following a failure of all four engines during the 1980s. Plenty of anecdotal evidence suggests that premature graying can be caused by great stress. And your mother might have been right when said you were the cause of her gray hairs.

According to a study published this past week in the journal Nature by Harvard University in Massachusetts, stress may play a crucial role in just how quickly hair goes from colored to ashen.

The researchers examined cortisol, the "stress hormone" that surges in the body when a person experiences a "fight or flight" response.

They examined how mice reacted to stress, finding out when the "fight or flight" response to danger kicks in. This response creates a biochemical response that can turn your hair gray.

This research study is the first to show a clear link between stress and graying hair.

Researchers said the study may also contribute to learning how stress affects different organs and tissues.

According to Ya-Chieh Hsu, a professor of Stem Cell and Regenerative Biology at Harvard, their research team was in search of the first scientific confirmation of the commonly held belief that stress can cause gray hair.

She said that everyone has an anecdote to share about how stress affects their body, particularly in their skin and hair. The skin and hair are the only tissues we can see from the outside.

Previous theories have reiterated that a specific type of stress somehow accelerates the aging process or triggers an autoimmune response. Stress activates a sympathetic nerve response that signals the stem cells responsible for coloring our hair. The hormones produced can deplete the melanocyte stem cells that determine hair color.

Thus, the culprit is the sympathetic nervous system.

The mice were studied to look at how stress affects stem cells in hair follicles. Hsu chemically induced stress in mice by injecting them with a compound called resiniferatoxin, which boosted the animals' stress hormone levels. This proved to be a reliable way of inducing the stress response over other strategies that the team explored, including using restraints such as tilting the animals' cages, wetting their bedding and changing their lighting conditions.

She noted that noradrenaline raises our heartbeat and allows us to react quickly to danger without having to think about it. Unfortunately, it is the same noradrenaline that turns out to be bad for melanocyte stem cells at a high level and triggers their loss.

Hair follicles are responsible for making melanocytes, the cells that give hair its color. As we age, melanocyte production is reduced which causes a person's hair to begin turning gray naturally.

According to Hsu, "The detrimental impact of stress that we discovered was beyond what I imagined." She said in a press release that after a certain number of days, all of the pigment-regenerating stem cells were depleted. You can't regenerate pigments anymore because the damage is permanent.