The hair can't actually turn white overnight, because all the hair is "dead", and the only way you can make its colour change is with dyes.
Hair gets its colour from a chemical called melanin, which is pumped in by cells at the base of the hair follicle. As your hair goes grey, these cells at the base stop making melanin. So some hairs will be their normal colour, but some (the ones without melanin) will be completely white. So here's a great truth - there's no such colour as grey hair. Grey hair is dark hairs, with the newer white hairs mixed in.
So how can somebody's hair turn white overnight? Easy, they first have grey hair (which is actually the mix of dark hair and white hair) - and then all the dark hair falls out over a few days.
This could be caused by a disease called alopecia areata , where your hair, for no apparent reason, simply falls out. Unlike common balding, alopecia areata is just as likely to happen in women as in men.
So if you've got grey hair, and those few remaining dark ones bail out, bingo - instant white hair! It can't happen overnight, but it can happen...
The well-accepted fact of the sudden changing of the color of the hair from violent emotions or other causes has always excited great interest, and many ingenious explanations have been devised to account for it. There is a record in the time of Charles V. of a young man who was committed in prison in 1546 for seducing his girl companion, and while there was in great fear and grief, expecting a death-sentence from the Emperor the next day. When brought before the judge, his face was wan and pale and his hair and beard grey, the change having taken place in the night. His beard was filthy with drivel, and the Emperor, moved by his pitiful condition, pardoned him. There was a clergyman of Nottingham whose daughter at the age of thirteen experienced a change from jet-blackness of the hair to white in a single night, but this was confined to a spot on the back of the head 1 1/2 inches in length. Her hair soon became striped, and in seven years was totally white.
Voigtel mentions the occurrence of canities almost suddenly. Biehat had a personal acquaintance whose hair became almost entirely gray in consequence of some distressing news that reached him. Cassan records a similar case. According to Rayer, a woman by the name of Perat, summoned before the Chamber of Peers, to give evidence in the trial of the assassin Louvel, was so much affected that her hair became entirely white in a single night.
Kondoru said:Or stress
Any well documented cases
Why does hair change colour anyway?
My aunt died in her 80s and her hair was brown edged with grey!
My hair started out blonde, and is now dark brown.
Kondoru said:My aunt died in her 80s and her hair was brown edged with grey!
rynner2 said:Oddly enough, I'm reading a crime book at present in which a US cop was once attacked with a knife to his head. His hair was partially shaved off so surgeons could repair the wound, but when it grew back he had a white streak in his dark hair.
Admittedly this is fiction, but maybe it was based on a real incident...
Crocker cites the case of a Spanish cock which was nearly killed by some pigs. The morning after the adventure the feathers of the head had become completely white, and about half of those on the back of the neck were also changed.
Meanwhile the show went on, and it became more of a road show than ever. Buffalo Bill’s Wild West played in more than 130 towns in both 1895 and 1896. In 1897, the Wild West played in Canada for the first time since Sitting Bull was a headliner in 1885. Annie admitted in 1899 that she had begun to at least think about retirement. The railroad travel was endless, and it had its dangers. Train accidents were not uncommon.
One notable wreck occurred at 3 a.m. on October 29, 1901, near Lindwood, N.C., while the company was headed to Danville, Va., for its last performance of the season. When the first section passed the switching station, the switcher thought that it was the whole outfit, so he threw the switch. The second section ran into an oncoming train. The wooden cars became so many piles of kindling as people and animals cried out in pain and steam hissed. Legend says that Annie Oakley, now 41, was found pinned beneath the rubble and it took several hours before she could be extracted. As Li’l Missie was carried by stretcher past some wounded horses that had to be shot, she supposedly remarked that she felt sorry for them. Just 17 hours after the wreck, according to legend, her brown hair turned totally white because of the horror of the accident.
Biographer Shirl Kasper, however, argues that Annie was not badly hurt in the wreck (the Charlotte Observer reported that nobody from the Wild West was injured) and that while Annie’s hair did turn white rather fast, it wasn’t because of the train wreck. Two newspaper articles in Annie’s scrapbooks at the Buffalo Bill Historical Center say that her hair turned white after she sat too long in a hot bath at a health resort later that year. In any case, says Kasper, it was her white hair, not any bodily injuries, that convinced Annie Oakley to immediately leave Buffalo Bill’s Wild West.
Martin graduated to opening for rock performers, where his long hair, scraggly beard, and hippie wardrobe aligned him firmly with the counterculture movement of the era. However, while in his twenties his hair began to go white; gradually, Martin began adapting his on-stage persona to fit the change, re-emerging as a clean-cut, immaculately dressed conservative.
Solving a biological puzzle: How stress causes gray hair
Scientists uncover link between the nervous system and stem cells that regenerate pigment ...
When Marie Antoinette was captured during the French Revolution, her hair reportedly turned white overnight. In more recent history, John McCain experienced severe injuries as a prisoner of war during the Vietnam War -- and lost color in his hair.
For a long time, anecdotes have connected stressful experiences with the phenomenon of hair graying. Now, for the first time, Harvard University scientists have discovered exactly how the process plays out: stress activates nerves that are part of the fight-or-flight response, which in turn cause permanent damage to pigment-regenerating stem cells in hair follicles.
The study, published in Nature, advances scientists' knowledge of how stress can impact the body. ...
In the hair follicle, certain stem cells act as a reservoir of pigment-producing cells. When hair regenerates, some of the stem cells convert into pigment-producing cells that color the hair.
Researchers found that the norepinephrine from sympathetic nerves causes the stem cells to activate excessively. The stem cells all convert into pigment-producing cells, prematurely depleting the reservoir.
"When we started to study this, I expected that stress was bad for the body -- but the detrimental impact of stress that we discovered was beyond what I imagined," Hsu said. "After just a few days, all of the pigment-regenerating stem cells were lost. Once they're gone, you can't regenerate pigment anymore. The damage is permanent."
The finding underscores the negative side effects of an otherwise protective evolutionary response, the researchers said.
"Acute stress, particularly the fight-or-flight response, has been traditionally viewed to be beneficial for an animal's survival. But in this case, acute stress causes permanent depletion of stem cells," said postdoctoral fellow Bing Zhang, the lead author of the study. ...
which the maintenance of somatic stem cells is directly influenced by the overall physiological state of the organism.Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells
Bing Zhang, Sai Ma, Inbal Rachmin, Megan He, Pankaj Baral, Sekyu Choi, William A. Gonçalves, Yulia Shwartz, Eva M. Fast, Yiqun Su, Leonard I. Zon, Aviv Regev, Jason D. Buenrostro, Thiago M. Cunha, Isaac M. Chiu, David E. Fisher & Ya-Chieh Hsu
Empirical and anecdotal evidence has associated stress with accelerated hair greying (formation of unpigmented hairs)1,2, but so far there has been little scientific validation of this link. Here we report that, in mice, acute stress leads to hair greying through the fast depletion of melanocyte stem cells. Using a combination of adrenalectomy, denervation, chemogenetics3,4, cell ablation and knockout of the adrenergic receptor specifically in melanocyte stem cells, we find that the stress-induced loss of melanocyte stem cells is independent of immune attack or adrenal stress hormones. Instead, hair greying results from activation of the sympathetic nerves that innervate the melanocyte stem-cell niche. Under conditions of stress, the activation of these sympathetic nerves leads to burst release of the neurotransmitter noradrenaline (also known as norepinephrine). This causes quiescent melanocyte stem cells to proliferate rapidly, and is followed by their differentiation, migration and permanent depletion from the niche. Transient suppression of the proliferation of melanocyte stem cells prevents stress-induced hair greying. Our study demonstrates that neuronal activity that is induced by acute stress can drive a rapid and permanent loss of somatic stem cells, and illustrates an example in
I only know* of the widow whose hair turned golden overnight!
*Dear Oscar told me.