Obesity has become a worldwide disease, posing a rapidly increasing challenge to the global healthcare system. The primary reason for obesity is that food intake exceeds the body’s needs. The central nervous system monitors the body’s energy status by continuously receiving peripheral gut-derived signals and functions as a master regulator in controlling feeding behaviors. Vagal afferents transmit gut-derived consumption signals from the periphery to the hindbrain (e.g., the nucleus of the solitary tract (NTS)). In contrast, vagal efferent nerves send commands to regulate peripheral organ activities. However, the precise role of the gut–vagus–NTS pathway and the gut–brain axis in regulating food intake is not yet fully understood. This review highlights the key roles of the NTS, vagal sensory neurons, and the gastrointestinal system in regulating feeding behaviors.