“I will fast … tomorrow”: Intentions to restrict eating and actual restriction in daily life and their person-level predictors

Objective: Dietary restraint is a common, yet controversial practice to tackle overweight. Yet, despite good intentions to reduce food intake, most restraint-based diets fail to produce long term weight loss. A better understanding of the naturalistic course of daily dieting intentions and their effectiveness in guiding subsequent eating behavior are therefore needed. Method: In two studies, participants (n = 49 and n = 59)reported both their state intention to restrict eating on the next day, as well as their actual restriction on that day via smartphone-based evening reports of 12 and 10 days, respectively. Intention-behavior gap scores were calculated as differences between intention at t1 (e.g. evening intention Monday for restriction Tuesday)and restriction at t2 (evening report of actual restraint on Tuesday). Restriction-related trait questionnaires served as predictors of general intention or restriction level, whereas several trait-level disinhibiting eating style questionnaires served as predictors for intention-behavior gaps (difference scores). Results: Daily intentions to restrict were rated higher than the daily actual restrictive behavior. Participants with higher scores on restriction-related questionnaires (restrained eating, dieting, lower intuitive eating)showed higher levels of daily state intention and restriction. Larger state intention-behavior gaps, by contrast, were seen in participants scoring high on trait-level disinhibiting eating styles (emotional eating, stress eating and food craving). Discussion: The results point to potential risk factors of diet failure in everyday life: emotional, stress eating, and food craving are disinhibiting traits that seem to increase intention-behavior gaps. These findings can inform individualized weight-loss interventions: individuals with disinhibiting traits might need additional guidance to avoid potentially frustrating diet failures.