Shaved hairs grow back thicker, faster or darker.

The “truth”

This belief is held optimistically by youths trying to grow moustaches, wearily by women taking a razor to their legs for the thousandth time, and desperately by balding men who haven’t had much luck with the goose fat and monkey hormones. But shaving cuts hair only at the surface of the skin – while it’s below the skin that hair growth takes place – so whatever you do to hair that’s already dead can have no effect on what’s coming up.

All authorities seem to agree on that much, but there are various theories to explain the illusion that shaved hair grows back stronger, including: small amounts of growth on a shaven face (or any other area of the body, come to that) are more noticeable than on a hairy face; because hairs taper, their shaved remnants are of greater diameter than long hairs, and blunt rather than soft, making them appear darker and thicker and feel coarser; hairs of uniform length look darker; changes in the length of growing hair are proportionally much greater the shorter the hair, making growth seem fastest soon after shaving; and newly-emerged hairs may be darker before the sun gets a chance to bleach them.