Habitual behavioural control moderates the relation between daily perceived stress and purging

AbstractObjectiveEvidence suggests that interpersonal stress plays a role in maintaining binge eating and purging (e.g., self‐induced vomiting, misuse of laxatives). Stress is especially likely to promote engagement in maladaptive behaviour if the behaviour is habitual; therefore, individuals whose binge eating and/or purging are habitual may be particularly likely to engage in these behaviours in the context of interpersonal stress. We aimed to investigate this hypothesis in a sample of women with binge eating and/or purging using ecological momentary assessment (EMA).MethodWomen (N = 81) with binge‐eating and/or purging symptoms completed a self‐report measure assessing habit strength of binge eating and purging followed by a 14‐day EMA protocol assessing daily perceived interpersonal stress and binge‐eating and purging episodes.ResultsHabit strength of purging moderated the within‐person effect of interpersonal stress on purging frequency, such that higher daily stress was associated with greater same‐day purging frequency when purging was more habitual. Contrary to expectations, the interactive effect of habit strength of binge eating and daily interpersonal stress on same‐day binge‐eating frequency was non‐significant.ConclusionsFindings suggest that individuals with habitual purging may be vulnerable to engaging in purging when they are experiencing high levels of interpersonal stress.