RESUMO
OBJECTIVE: Prominent theories of binge-eating (BE) maintenance highlight dietary restriction as a key precipitant of BE episodes. Consequently, treatment approaches for eating disorders (including binge-eating disorder; BED) seek to reduce dietary restriction in order to improve BE symptoms. The present study tested the hypothesis that dietary restriction promotes BE among 112 individuals with BED. METHODS: Participants completed a 7-day ecological momentary assessment (EMA) protocol before and after completing 17 weeks of either Integrative Cognitive-Affective Therapy or guided self-help cognitive behavioral therapy. Analyses examined whether dietary restriction on 1 day of the baseline EMA protocol predicted risk for BE later that same day, and on the following day. Changes in dietary restriction over the course of treatment were also evaluated as a predictor of change in BE from pre-treatment to post-treatment. Baseline dietary restraint was examined as a moderator of the above associations. RESULTS: Dietary restriction did not predict BE later the same day, and changes in restriction were not related to changes in BE across treatment, regardless of baseline dietary restraint levels. Restriction on 1 day did predict increased BE risk on the following day for individuals with higher levels of dietary restraint, but not those with lower levels. DISCUSSION: These findings challenge the assumption that dietary restriction maintains BE among all individuals with BED. Rather, results suggest that dietary restriction may be largely unrelated to BE maintenance in this population, and that reducing dietary restriction generally does not have the intended effect on BE frequency.
RESUMO
OBJECTIVE: The present study sought to characterize the temporal patterns of binge eating and theorized maintenance factors among individuals with binge-eating disorder (BED). METHOD: Ecological momentary assessment of 112 individuals and mixed-effects models were used to characterize the within- and between-day temporal patterns of eating behaviors (binge eating, loss of control only eating, and overeating only), positive and negative affect, emotion regulation difficulty, and food craving. RESULTS: Risk for binge eating and overeating only was highest around 5:30 p.m., with additional binge-eating peaks around 12:30 and 11:00 p.m. In contrast, loss of control eating without overeating was more likely to occur before 2:00 p.m. Risk for binge eating, loss of control only eating, and overeating only did not vary across days in the week. There was no consistent pattern of change in negative affect throughout the day, but it decreased slightly on the weekend. Positive affect showed a decrease in the evenings and a smaller decrease on the weekend. The within-day patterns of food craving, and to some extent emotion regulation difficulty, resembled the pattern of binge eating, with peaks around meal times and at the end of the night. DISCUSSION: Individuals with BED appear most susceptible to binge-eating around dinner time, with heightened risk also observed around lunch time and late evening, though the effects were generally small. These patterns appear to most strongly mimic fluctuations in craving and emotion dysregulation, although future research is needed to test the temporal relationships between these experiences directly. PUBLIC SIGNIFICANCE: It is unknown which times of the day and days of the week individuals with binge-eating disorder are most at risk for binge eating. By assessing binge-eating behaviors in the natural environment across the week, we found that individuals are most likely to binge in the evening, which corresponds to the times when they experience the strongest food craving and difficulty with regulating emotions.
