If you think you’ve gone grey from the stress, you could be right, according to a new study. It has been argued that going grey early on is caused by genetics, but scientists have found stress really does make you grey.
The research team, who published their findings in science journal PLOS Biology, found that when the body gets stressed, such as fighting a virus or bacteria, this has a double-effect.
As well as our immune system kicking into gear, it also triggers changes in the cells in hair follicles which produce colour. This in turn makes our hair turn silvery or grey.
Grey hair is hair without pigment, and it could be regarded as the hairs’ natural state. When we are younger, our hair is coloured by the pigments produced by cells in the hair follicle known as melanocytes.
As we grow older, the melanocytes gradually become less active, so less pigment is produced, the colour fades, and grey hair grows instead.
But, researchers from the University of Alabama in Birmingham found the “surprising” link between genes that control hair colour and genes that signal to our bodies it’s time to fight off an infection.
The study, carried out on mice, found that when the body is under attack our cells produce chemical signals called interferons. These interferons make our cells’ machinery undergo changes that ward-off viruses and generally boost defences.
But the unexpected side effect of the defence system is that it turns off cells that produce hair colour.
William Pavan, study co-author and researcher at the National Institute in Health said: “This new discovery suggests that genes that control pigment in hair and skin also work to control the innate immune system.”
He added: “These results may enhance our understanding of hair greying.”
As well as ‘turning off’ hair colour, it can also turn off colour in the skin, leading to the disease vitiligo, which occurs when pigment-producing cells die or stop functioning.
“More importantly, discovering this connection will help us understand pigmentation diseases with innate immune system involvement like vitiligo,” he said.
Vitiligo, which causes discoloured skin patches, affects between 0.5 percent to 1 per cent of all humans.