A team of Yale University researchers took an interesting approach to tackling the obesity epidemic, viewing the brain, rather than the mouth, as the root of the problem. According to lead researcher Xiaoyong Yang, obesity is largely connected to an inability to respond to hunger, so theoretically if we could control the response, on a neurological level, then we could control obesity. In their latest study, the Yale researchers may have just turned this theory into a reality.

Yang and his team studied overweight and obese mice and found that they shared a similar characteristic with humans, who also carried extra body fat: They were unable to stop eating even after the sensation of hunger was long gone. This inability to stop eating isn’t as much of a free choice as it is a neurological dysfunction. “Although there is plenty of food and plenty of energy, the hunger neurons send a false message that the body needs to conserve energy, not burn it,” explained Yang, as reported by Time.

Researchers have long identified two distinct classifications of body fats: white fat and brown fat. Brown fat is a type of energy-burning heat creating fat that is found in the chubby little legs of newborns. This fat dissipates chemical energy as heat, according to a press release. As the children age this brown fat, which gets its coloring from its rich concentration of mitochondria, it's converted into white fat, the fat you find in the not as cute chubby legs of adults.

In their study, which is currently published in the journal Cell, the team demonstrated in animals that the neurons in the brain that control appetite also control the “browning” of white fat. “This work indicates that behavioral modifications promoted by the brain could influence how the amount of food we eat and store in fat is burned," Yang said.

The team found that when mice are temporarily deprived of food, their brain goes into starvation mode and sends signals to the body to conserve energy. This energy conservation was also found to be intrinsically linked to the brain’s “hunger” messages and prompted the mice’s bodies to store the white fat rather than convert it to energy-rich brown fat.

“We showed that hunger itself is a signal that controls the browning of white fat, so the brain can actually control the browning of white fat,” Yang said. Eventually, this finding could be used to reexamine the brains of obese people and help them deal with hunger more effectively, an idea which Yang referred to as “a promising possibility,” in his Cell Paper Clip.

Source: Yang X, Ruan H, Dietrich MO, et al. O-GlcNAc Transferase Enables AgRP Neurons to Suppress Browning of White Fat. Cell. 2014.