Food intake and addictive-like eating behaviors: Time to think about the circadian clock(s).

Compulsive feeding has been considered as an addicted-like behavior with similarities to drug addiction. Food intake is brain controlled involving a balance between metabolic and hedonic pathways that modulate respectively how much and what is eaten. Pathological conditions such as compulsive feeding or an eating addiction can interfere with this balance and obesity may develop. Daily feeding times are also centrally controlled by the circadian clock in the suprachiasmatic nucleus. Disruptions of this body clock (e.g., social jet-lag, shift work) lead to eating and metabolic disorders. The circadian pacemaker is intricately connected with the metabolic and hedonic centers controlling feeding, and most importantly, some of these nuclei have clock activity. When the brain circadian system is compromised in eating disorders, such perturbations may be in part the causes of compulsive feeding, night eating and addictive-like eating behavior. Therefore, food intake is regulated by the central circadian-metabolic-hedonic network, which is functionally interconnected to avoid perturbing the eating behavior physiology.