Food preference and behavioural choice across the eating disorder and body weight spectrum

Eating disorders (EDs) such as Anorexia Nervosa (AN), Bulimia Nervosa (BN), and Binge-Eating Disorder (BED) share overlapping symptoms, risk factors, and maintenance mechanisms, yet differ in their behavioural manifestations. This study aimed to investigate binary food choice behaviour across EDs and weight groups, including healthy controls with normal weight, overweight and obesity in a controlled laboratory setting.

N = 189 individuals with AN (n = 40), BN (n = 29), BED (n = 24) as well as controls without eating disorders with normal weight (HC-NW, n = 57), overweight (HC-OW, n = 18) and obesity (HC-OB, n = 21) made 153 binary food choices while decision times were recorded. Participants also rated foods on liking and calorie content. The number of calories in chosen foods, the relationship between calorie content and liking ratings and decision times were analysed. We further explored the roles of eating styles, BMI and ED symptoms in food choice.

Individuals with AN chose less calories, liked lower-calorie foods more and made faster decisions, especially for lower-calorie options compared to HC-NW. The other groups did not differ from HC-NW in food choice or liking, but BN - and to a lesser degree HC-OB and HC-OW - made faster food choices. External eating positively predicted higher-calorie choices.

This study underscores the distinctiveness of AN in food choice behaviour and the need for transdiagnostic approaches to understand shared and unique mechanisms across EDs and weight groups. Future research should explore longitudinal changes in food choice processes and integrate contextual and emotional factors to better capture the complexity of eating behaviours.