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Scientists have found that stress turns our hair grey, white or silver in mice. Stem cell biologists from Harvard University did a series of tests on mice to find the effects of stress on them. The scientists injected the mice with the ingredient in chili peppers that gives them their heat. This made the mice stressed. It caused a hair-colouring pigment in the mice to overwork as a reaction to the stress. It used up all colour-regenerating stem cells and the mice's hair rapidly turned white. A researcher said: "The detrimental impact of stress that we discovered was beyond what I imagined."
For centuries, people have believed that stress turns hair grey. France's Queen Marie Antoinette's hair supposedly turned white the night before she was beheaded during the French Revolution. More recently, the hair of presidents and other world leaders have quickly lost colour. The strains of leadership have gone to the roots of things, especially hair follicles. The researcher said the loss of the pigment-regenerating stem cells cannot be reversed. She said: "You can't regenerate pigment any more. The damage is permanent." She thinks stress could accelerate the aging process.
Back to the greying hair lesson.