Past studies have shown that bald men still have the stem cells that create hair, one researcher noted to Bloomberg News. The once-flourishing follicles are there as well, but they’re smaller and produce thinner, smaller hairs; the hair over time simply becomes too weak to punch through the scalp. So if PGD2 is stunting that growth, then blocking the protein’s receptor could mean that some or all of the hair returns. As luck would have it, there are drugs already being tested for other conditions, such as allergies and facial flushing, that inhibit PGD2.

Male-pattern baldness affects tens of millions of men in America, and about 80% of white men before they hit age 70. The erosion can start in one’s teens but is more likely to occur later on; according to the National Library of Medicine, more than 50% of men over the age of 50 have some amount of hair loss. The results from this study could be mane-changers, though as with so many promising findings, treatments based on them are still years away.