Going Gray? The Causes Are Not So Black-and-White

Graying of hair (scientifically known as canities) has genetic roots but affects nearly everyone who lives long enough. It’s been blamed on all sorts of things, including “paroxysms of rage, unexpected and unwelcome news, habitual headaches, overindulgence in sexual appetite, and anxiety,” according to an early 19th-century French dermatologist. What makes hair turn gray? Graying […]

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