When scientists gave a specific fat chemical (15-HETE) to mice whose heat production was blocked, it brought back their ability to burn fat and generate heat, even if the bacteria or enzyme blocking it were still present.

When scientists grew fat cells with this specific bacteria (Sphingomonas), the cells stopped making a key fat-burning chemical and heat-producing proteins—but when they used a different common bacteria (E. coli), nothing changed.

In mice, a type of gut bacteria called Sphingomonas paucimobilis moves to belly fat during inflammation and blocks the body’s ability to burn calories for heat by interfering with a key fat-burning chemical and its signaling pathway.