Developing an Integrated Framework of Eating Behaviour Traits: Evaluating their Associations with Energy Intake and Weight Change

Motivations for under or overeating are influential in shaping eating behaviours, and understanding these motivations may help to increase healthy eating and/or prevent dysfunctional eating. Eating behaviour traits (EBT) are self-report measures of eating behaviour constructs, that are used to quantify individual differences in motivations to eat. However, the multitude of EBTs has led to confusion, due to overlap between constructs, theories and proposed mechanisms of action. Research is needed to clarify the current measures of EBTs, how they relate to each other and how they relate to external outcomes. This thesis develops a comprehensive framework of EBTs and examines how it relates to existing theory and its ability to predict external outcomes.

Paper One proposes a provisional framework of EBTs, including three-factors which integrate knowledge from dual-process theory. Paper Two identifies existing EBTs and found that EBTs significantly predict short-term energy intake and longer-term energy balance (Body Mass Index; BMI). Susceptibility to hunger, disinhibition and binge eating (‘reactive’ EBTs) were the strongest predictors. Paper Three utilised the strongest predictors along with restraint (‘restricted’ EBT), and measures of homeostatic eating (‘homeostatic’ EBTs), in a weight loss maintenance trial. The results found reactive, restricted and homeostatic EBTs were associated with weight change. Paper Five and Paper Six apply factor analysis to multiple EBT constructs (paper 5) and their individual items (paper 6) and found support for a 6-7-factor model of EBTs, including reactive eating, negative emotional eating, positive emotional eating, restricted eating, homeostatic eating, eating for pleasure and eating for health. Across diverse samples, the framework was significantly associated with BMI and weight change. This thesis supports the use of a framework of EBTs, and highlights the development of a brief EBT domain survey as a measurement tool, to improve eating behaviour tracking and outcomes of research and weight management interventions.