For centuries, it has been widely believed that fright or dread can turn hair white. “They say” that the hair of some condemned prisoners (such as Marie Antoinette) turned white the night before their executions. Curiously, there are no modern reports from death row of this happening. Ghost stories also often describe people whose encounters with spirits left them with white hair.
It is the stuff of universal legend, folklore , and myth. But is it true?
It is in fact medically impossible; there is no mechanism by which hair could organically turn white, either suddenly or overnight. Despite manufacturer suggestions that certain products can restore life to hair, hair is always dead. Once the hair grows out of the head, it can’t be influenced by any psychological or physiological processes in the body (including scares or shocks).
Even if an illness, injury, or sudden shock could turn hair white, it would be weeks before the effect would be visible because only the root would be affected. You can see this same principle when a person injures a fingernail near the cuticle, and the damaged part gradually grows out. It’s no more possible for the whole hair shaft to spontaneously turn white than it is for a dead tree branch to sprout leaves. Gray hair might appear to turn white if the colored hair shafts selectively fell out for some reason (for example, the medical condition alopecia), leaving the white hairs behind.
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