Giving an antioxidant called NAC in drinking water helped slow down hair greying in mice that were genetically prone to it, possibly by reducing harmful molecules in their bodies.

In mice with a genetic problem that causes gray hair, giving them an antioxidant called NAC in their water seems to help keep their fur from turning gray by protecting the cells that give hair its color.

Giving mice a special water with NAC for 50 days helps fix their fading fur color by reducing harmful chemicals in their hair follicle stem cells and bringing back some of the cells that make pigment.

In mice with a specific genetic problem, hair turns gray because the stem cells that make hair color die off first—not because the color-making process itself is broken.

When a certain gene is turned off in hair color cells in mice, their fur starts to gray early because the cells die off — but the ones that survive can still make pigment just fine.

When a certain gene is turned off in mice, it damages the stem cells that give hair its color—but not the regular color-making cells—so the hair gradually loses pigment and turns gray or white.