Keep it on: How complex diet rules prevent weight loss

Abstract

We investigated the impact that the cognitive complexity of diet rules has on adherence to weight loss diets. The underlying assumption guiding this research was that popular weight loss diets can fail at the individual level if they are too complicated from a cognitive point of view, meaning that dieters are not able to recall or apply all required information. The impact of excessive cognitive demands on diet compliance and dieters’ perception of diet rule complexity were investigated (1) from an environmental perspective, by analysing diet environments (i.e., diet rules in diet books), and (2) from the perspective of the dieter in an online-questionnaire. First results suggest that diets with more complex diet rules correlate with lower adherence rates from clinical trials examining popular weight loss diets. In our longitudinal study with more than 1200 participants who are trying to lose weight, we show that perceived difficulty reported at the first measurement point predicts quitting of the diet prematurely (i.e., before goal weight or time planned to be on diet are reached) at later points in time.