Hair gains its color from two kinds of melanin pigment; one is eumelanin that determines how dark the hair is, and second is pheomelanin that dictates how red or yellow it is. When one ages, the cells that produce these pigments in hair follicles stop functioning and result in colour-less hair. Everyone gets obsessed with white hair. But what about the hair that turns white overnight? Canities Subita is the term used for hair turning white overnight. The world considers this as myth but the International Journal of Trichology conducted study in 2013 and found 84 reports of speedy adult hair blanching between 1800 and the present day. As mentioned at www.theatlantic.com, Michael Nahm (who was the lead author of the 2013 study) says that “All these accounts support the notion that sudden whitening does indeed happen. Although we still don’t know how exactly it occurs. It remains an under-investigated phenomenon”.
Experts say that it is the stress and troubles that are responsible for whiten hair. It has nothing to do with the age. In other words, one can get white hair even in young of age. French nobleman Pierre de Bourdeille told about French Queen Marie Antoinette whose hair turned white the night before her execution. He said “It was not old age that had turned it white. But the troubles, misfortunes, and sorrows which she had suffered, especially in her prison.” She was killed in 1587 at age 44 and her executioner showed her head to the crowd, and revealed her short-cropped white hair. The nobleman statement is worth mentioning here “Psychosocial stress can’t affect the hair fiber that’s already formed. It can only affect the fibers as they are forming.”
The same thing happened with Captain Eric Moody whose hair turned white within six months of the incident when the four engines of his plane failed and he had to make emergency landing at Jakarta airport. Within a year the rest of his hair had done the same.
How does this happen is still not clear. Experts say that the same chemical used to bleach hair from bottles also turns hair greys. An enzyme called catalase break down hydrogen peroxide produced by Melanin-making cells. As we age, production of the enzyme drops and hydrogen peroxide built-up and block production of melanin.
Above-mentioned examples make clear that a severe shock or stress can trigger hair loss or hair pigment fall out. According to the BBC, it is necessary to examine the hair before and after a shocking incident in order to understand the hair-turn-to-grey story. It said “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”
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