linguistic:translation
Stress

Anecdotes report that stress, both chronic and acute, may induce achromotrichia earlier in individuals than it otherwise would have. There is some evidence for chronic stress causing premature achromotrichia, but no definite link has been established. It is known that the stress hormone cortisol accumulates in human hair over time, but whether this has any effect on hair color has not yet been resolved. A 2020 paper, published in the journal Nature reported that stress can cause hair to lose its pigment. An overactive immune response can destroy melanocytes and melanocyte stem cells in black-haired rats. When intentionally subjecting them to panic, they bleached their coat. The next time the rats' coat grew, there were no melanocyte stem cells in these damaged follicles, so white hairs sprouted, and the color loss was permanent.