Energy homeostasis is a complex on-going process that includes maintaining immediately available as well as stored nutrient levels at optimal levels given the environment. To accomplish this, the brain receives continuous information about stored energy and current and anticipated fluxes in critical organs, as well as about food that is potentially available or being eaten and absorbed. The brain in turn determines when and how much food will be consumed, balancing this activity with other behaviors. This review discusses hormonal and related satiety signals generated as food is being consumed, and upon adiposity signals related to the amount of fat stored in the body, that influence energy intake and ultimately body weight.