Eveningness and bulimic behavior

Previous research suggests that evening constitutes a high-risk environment that increases the probability of binge eating and purging. Individual differences in morningness–eveningness are associated with differing levels of exposure to evening versus day, with “night people” spending a larger portion of their waking lives during the evening and a smaller portion of their waking lives during the day than do “day people”. This study tested the hypothesis that greater eveningness is associated with greater binging and purging. One-hundred and fifty-one undergraduates completed the Composite Scale of Morningness–Eveningness, the Bulimia Test-Revised, the Bulimia Scale of the Eating Disorders Inventory, and measures of several other variables. Results showed that eveningness was correlated moderately and positively (rs=0.24) with both measures of bulimic behavior; these correlations were reduced only slightly after controlling for other study variables. It is argued that exposure to the dimmer lighting of evening promotes general behavioral disinhibition, thus undermining self-regulatory control and adherence to oneʹs dietary standards, resulting in the disinhibited eating that is the hallmark of bulimia.