TL;DR
Gray hair has always been the one sign of age that seemed to run in only one direction. That is starting to look negotiable. This summer, dermatologists in Madrid reported that a melatonin solution rubbed on the scalp every day brought partial color back to gray hair in 4 of 20 patients within three months. A 141-person, placebo-controlled trial of minoxidil, a drug already used against hair loss, has finished in China, and a company has listed a 240-person late-stage trial of its own gray-hair drug. Underneath it all, lab work in mice has worked out why the pigment-making stem cells in each hair follicle quit, which points to how to restart them. Our odds that a treatment beats placebo at bringing gray hair's color back: a 75% chance it works, likely by 2029. To see the full odds and the timeline of breakthroughs between here and a head of natural color, subscribe.
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