Scientists discover natural hormone that reverses obesity (opens in new tab)

A hormone called FGF21 can reverse obesity in mice by activating a newly identified brain circuit tied to metabolism. Surprisingly, it works in the hindbrain—the same region targeted by GLP-1 drugs like Ozempic and Wegovy—but through a completely different mechanism. Instead of suppressing appetite, FGF21 ramps up the body’s energy burning. This insight could pave the way for more targeted weight-loss and liver disease treatments.