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Scientists have that stress is one factor in turning our hair grey, white or silver - at least, in mice. Stem cell biologists from Harvard University in the USA a series of tests on mice to the effects of stress on the rodents. The scientists the mice with an ingredient in chili peppers that gives them their heat. The compound the mice stressed. This a hair-colouring pigment in the mice to go into overdrive as a reaction to the stress and colour-regenerating stem cells. This caused the mice's hair to rapidly turn white. Lead researcher, Professor Ya-Chieh Hsu, said: "The detrimental impact of stress that we was beyond what I ."

People have for centuries about the link between stress and greying hair. It is that France's Queen Marie Antoinette's hair turned white the night before she was during the French Revolution in the late-eighteenth century. More recently, we have the locks of presidents and other world leaders quickly lose color. The strains of leadership seem to to the roots of things, especially hair follicles. Professor Hsu said the loss of the pigment-regenerating stem cells cannot reversed. She said: "Once they're , you can't pigment any more. The damage is permanent." Worryingly, she that stress could responsible for accelerating the aging process.

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