HTR2A and psychiatric disorder: One of the interesting links to mental illness from the nutritional and pathological points of view are the 5-HT2A and 5-HT2C receptors, seven-transmembrane, G-protein linked receptors positively coupled to phospholipase C. 5-HT2A receptors are involved in the regulation of learning and memory [5], and 5-HT2C receptor signaling is related to physiological brain functions, such as regulation of appetite, food intake and energy balance, stress response or sleep regulation [6].