Feeding and Eating Disorders in the Context ofCircadian Rhythms

Abstract

A circadian rhythm is a 24-hour rhythm controlled by a master clock, the suprachiasmaticnucleus, and driven by synchronizing internal/external zeitgebers. Food intake is one ofthe most important external cues/zeitgebers. Studies in humans and animals have shownthat misalignment of food intake leads to chronodisruption, which is associated with met abolic disruption, obesity, and disordered eating attitudes. The term chronotype, whichexpresses the circadian typology, has been classified into 3 main types that represent thedifferences in the reflection of circadian rhythms shown in human studies on daily behav iors. It has been reported that evening-type individuals are more prone to disrupted eat ing attitudes, such as skipping meals, eating at night, and consuming a calorie-rich diet. Inaddition, eating disorders up to the diagnostic level is associated with the evening type.The bidirectional relationship between impaired circadian rhythms and disordered eat ing attitudes has brought chronotherapeutic interventions, which are biological rhythm oriented treatment approaches, to the agenda. Bright light therapy has been found toreduce bulimic eating behaviors and night eating symptoms. More evidence is neededregarding the effect of chronotherapeutic approaches on metabolic disorders, disorderedeating attitudes, and eating disorders associated with obesity.