A 2025 study from the University of Southern California discovered that neurons in the ventral hippocampus store detailed memories of meals—what you ate and when. These brain “engrams” communicate with hunger centers, helping you feel full between meals.

A 2025 feasibility trial by Meinlschmidt et al. studied 54 women with and without obesity after a 10-hour daytime fast. Both groups reported increased hunger and lower satiety, but mood effects differed: women with obesity experienced more depression and anger, while non-obese women mainly reported increased fatigue.