(PS6-A1) Difficulties in Emotion Regulation Moderate the Longitudinal Association Between Negative Affect and Dieting Behavior

Previous research in both non-clinical and eating disorder samples has established a strong association between emotion regulation deficits and greater disordered eating, particularly for binge eating and compensatory behaviors. According to the affect regulation model, individuals engage in disordered eating in the form of binge/purge behaviors to manage negative emotions. Emotion regulation difficulties may impact this association such that individuals with higher emotion regulation difficulties may be more likely to engage in disordered eating as compared to individuals with greater skill use. More recently, researchers have extended this model from binge/purge spectrum behaviors to restrictive behaviors, such that restrictive behaviors may also serve to manage negative emotions. However, most of the research linking emotion regulation deficits, negative affect, and dietary restriction has been cross-sectional, which is unable to assess the longitudinal relationships between negative affect and restrictive behaviors. In the current study undergraduates (N=1011) enrolled in a daily diary study completed assessments at baseline and once daily over seven consecutive days that measured emotion regulation difficulties, negative affect, and dieting behavior. Results from the logistic multi-level model indicated that baseline difficulties with emotion regulation (OR = 2.90, 95% CI [1.91, 4.41], p < .001), average negative affect over the week (OR = 5.10, 95% CI [3.14, 8.26], p < .001), and daily negative affect (OR = 3.18, 95% CI [2.18, 4.62], p < .001) were associated with higher probability of engaging in dieting over time. The main effect of daily negative affect was qualified by significant interactions with both difficulties in emotion regulation and average negative affect. Individuals whose average negative affect was high were more likely to diet overall but at the highest levels of state negative affect, individuals were more likely to diet, regardless of their average negative affect (OR = 0.32, 95% CI [0.19, 0.54], p < .001). Further, individuals who endorsed higher emotion regulation difficulties at baseline were more likely to diet in the context of high daily negative affect (OR = 1.62, 95% CI [1.04, 2.54], p = .034). The current findings support prior cross-sectional research that negative affect is associated with greater restrictive eating behaviors, and that this association is moderated by emotion regulation difficulties. These results suggest that emotion regulation difficulties play a role in restrictive eating behavior and may have a similar emotion regulation function longitudinally as hypothesized for binge/purge spectrum behaviors. Future research should examine how daily changes emotion regulation difficulties may interact with negative affect and dietary restriction.