But this doesn’t explain other anecdotal tales, for instance in young people who would have so few white hairs that if all their darker hair fell any white hairs remaining would be very sparse. Then there’s a more recent case study of a 54-year-old woman in Switzerland who had a small patch of hair loss. She was given steroids, which treated the hair loss successfully, but within a few weeks all her hair had turned white, even though she had not had a frightening experience and had stopped losing her hair.
Last year, a study from a research group led by no less than one of this year’s recipients of the Nobel prize in Chemistry, Robert Lefkowitz, offered some clues. They outlined a mechanism through which a hallmark of chronic stress causes DNA damage in mice that could lead to conditions like greying hair.
The puzzle of whether your hair can turn grey sounds like a simple one for medical science to solve, but it’s not. Ultimately, to study exactly what happens you would need to examine the hair before and after a shocking incident, carefully assessing its colour and thickness. Life-threatening situations are not only rare, but unpredictable and no ethics committee is going to let you induce a sufficiently terrifying experience in a lab volunteer.
Yet there is something about the idea of hair changing colour through shock that is fascinating. Maybe it’s the idea that the body reveals more than we think, that underneath the impressive calmness which allowed Captain Moody to save the lives of 247 passengers, his body was telling a different story.
You can hear more Medical Myths on Health Check on the BBC World Service.
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