As per new revelation it is said that acute stress can lead to hair going grey prematurely. Stress can be measured as a form of speeded ageing.
Stress distresses the whole body, scientists first had to narrow down which body system was responsible for connecting stress to hair color. The team first conjectured that stress causes an insusceptible attack on pigment-producing cells. Hence, researchers polished in on the sympathetic nerve system, which is responsible for the body's fight-or-flight response.
Sympathetic nerves branch out into each hair follicle on the skin. Sympathetic nerves are found in every hair follicle, and when the body is under stress they release a hormone called noradrenaline which is taken up by melanocytes. Some stem cells present in the hair follicles change to melanocytes when hair needs to be regenerated. What excess noradrenaline does though is overstimulate the stem cells and convert all of them to melanocytes. The reservoir of stem cells that can pigment the hair is therefore exhausted too soon and can't be regenerated. As a result, the hair that sprouts from the follicle is in loss of color and appears grey.
Like any good study, it may represent an important striding step toward rationalizing and developing pharmaceutical fountains of youth.