November 15, 2007
Does stress turn your hair grey?:
Scientific American has a short article which examines whether there's any truth to the common theory that stress makes your hair go grey. It's turns out there's some circumstantial evidence that stress may have an effect, but no definite causal link has been found.
Apparently, the gradual loss of melanocyte stem cells, ones that are key for hair colouring, lead to the loss of pigment.
Does stress accelerate this demise of the melanocyte population? "It is not so simple," Fisher says, noting that the process of graying is a multivariable equation. Stress hormones may impact the survival and / or activity of melanocytes, but no clear link has been found between stress and gray hair. Suspicions — and hypotheses — abound, however.
"Graying could be a result of chronic free radical damage," says Ralf Paus, professor of dermatology at the University Hospital Schleswig-Holstein in Lübeck, Germany. Stress hormones produced either systemically or locally (by cells in the follicle) could produce inflammation that drives the production of free radicals — unstable molecules that damage cells — and "it is possible that these free radicals could influence melanin production or induce bleaching of melanin," Paus says.
"There is evidence that local expression of stress hormones mediate the signals instructing melanocytes to deliver melanin to keratinocytes," notes Jennifer Lin, a dermatologist who conducts molecular biology research at the Dana-Farber / Harvard Cancer Center in Boston. "Conceivably, if that signal is disrupted, melanin will not deliver pigment to your hair."
And general practice physicians have observed accelerated graying among patients under stress, says Tyler Cymet, head of family medicine at Sinai Hospital in Baltimore, who conducted a small retrospective study on hair graying among patients at Sinai. "We've seen that people who are stressed two to three years report that they turn gray sooner," he says.
Link to SciAm article 'Fact or Fiction?: Stress Causes Gray Hair' (via 3Q).
