Mechanisms of emotional eating: food approach bias covaries with affect on days with high food craving

Emotional eating (EE) - eating in response to emotions rather than hunger - has high clinical relevance, yet its underlying mechanisms (how?) remain poorly understood. Further questions relate to interindividual differences (who?), and the specific foods (what?) around which EE occurs. To address ‘how’, we investigate whether reaction time-based food approach biases – reflecting motivational tendencies – covary with affect in daily life. To address ‘who’ and ‘what’, we consider trait EE alongside hedonic and goal-related food characteristics. In 76 participants with dietary goals, we measured positive and negative affect and approach bias towards goal-congruent and -incongruent foods on nine midday assessments using ecological momentary assessment and a mobile approach-avoidance task; hedonic food characteristics were assessed with food-specific craving ratings in the evening. Trait EE was assessed using the Salzburg Emotional Eating Scale. There was no direct association between affect and approach bias, nor one moderated by goal-congruency. Instead, affect and approach bias covaried on days with high craving: negative affect was linked to higher approach bias, while positive affect was linked to lower approach bias, especially in participants reporting more intake during negative affect or less intake during positive affect (trait EE), respectively. Our results indicate temporally dynamic relationships between affect and approach biases (how?) that did not emerge as a function of specific food characteristics (what?) but on high craving days (when?) – particularly in trait emotional eaters (who?). Hence, eating behavior might be altered through food approach tendencies during hedonic states opening avenues for mechanistic research and context-sensitive eHealth treatments.