Predicting success and failure at the regulation of eating behaviours: Relations between women's regulation styles and food planning strategies

Abstract

Recent studies based on self-determination theory (Deci & Ryan, 2002) have found that autonomous regulation is linked to healthy eating behaviours, while controlled regulation is linked to dysfunctional eating behaviours (Pelletier, Dion, Slovinec-D'Angelo, & Reid, 2004). The main purpose of this thesis was to build on this previous work by examining the relations between regulation styles for eating behaviours and approach vs. avoidance food planning strategies in order to better understand success (healthy eating behaviours) and failure (bulimic symptoms and failure at weight-loss) at the regulation of eating behaviours. In total, three studies were conducted. In the first study, a new scale was developed to assess approach food planning and avoidance food planning, namely the Planning of Eating Behaviours Scale (PEBS). Results from confirmatory factorial analyses supported the two-factor structure of the scale. In addition, construct validity was assessed through correlations between the PEBS subscales and measures of well-being. In Study 2, mediational analyses were performed to examine whether approach and avoidance food planning could account for the effects of regulation styles on eating behaviours. Results indicated that approach food planning is a partial mediator of the relation between autonomous regulation and healthy eating behaviours, such that women with autonomous regulation are more likely to use approach food planning, which in turn is positively associated with healthy eating behaviours. Avoidance food planning was identified as a partial mediator of the relation between controlled regulation and dysfunctional eating behaviours (e.g., bulimic symptoms and food concerns), such that women with controlled regulation are more likely to use avoidance food planning which in turn is more likely to lead to dysfunctional eating behaviours. Finally, Study 3 examined whether two types of planning interventions alter the relationship between regulation styles and the outcome of the regulation. The approach-oriented intervention made women with high levels of autonomous regulation more successful at weight loss. Results also indicated a main positive effect for autonomous regulation on body weigh goal attainment and healthy food choices. The avoidance-oriented intervention was found to have no impact on measures of success, whether on its own or in interaction with regulation styles.