Scientific American looks into whether stress really causes gray (or grey, if you prefer) hair. From the article –

“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.”

Full article here — Fact or Fiction?: Stress Causes Gray Hair

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