When you're stressed, a specific part of your brain sends a signal to your liver to make more sugar, and this happens because your body's 'fight or flight' system gets turned on.

When mice get suddenly scared or stressed, a specific part of their brain sends a signal to their liver to quickly make more sugar, and this happens without needing their stress hormones or insulin/glucagon from the pancreas.

When you're stressed, two types of brain cells in a specific area send signals to another part of the brain that tells your body to raise your blood sugar — even though one type excites and the other inhibits, both can make your blood sugar go up.

When mice are stressed over and over, their brain’s stress response system gets duller, so they stop spiking their blood sugar when scared—and eventually end up with high blood sugar and weight gain, especially if they eat a lot of fatty food.

When scientists turn on a specific brain circuit in mice that connects fear and stress areas to the metabolism control center, the liver starts making more sugar from scratch—even though the stored sugar in the liver doesn’t change.