Obesity: Homeostatic regulation and hedonic aspect of food intake

Compelling evidence supports the primary role of the diet and metabolic regulation of food intake in the establishment of metabolic diseases. This review describes the hypothalamic and brainstem structures involved in the control of food intake. The arcuate nucleus (AN) is a metabolic relay receiving the metabolic signals from the periphery and projecting to the paraventricular nucleus (PVN) and lateral hypothalamus (LH), which are involved in the sensation of satiety and hunger, respectively. Also, the role of the solitary tract nucleus (STN) in the regulation of food intake is discussed herein. Food intake is not controlled only by the structures associated with the vegetative life but also by structures of hedonism that often incites individuals to consume palatable foods. The emotion towards the food created at the level of the central amygdala (CeA) arrives at the nucleus accumbens (Nacc), which projects to the ventral tegmental area (VTA) in order to increase the production of dopamine that is suppressed by the prefrontal cortex (PFC). This review addresses the intervention of these structures in food intake by evoking the state of addiction to the diet observed in people with obesity.