The central role of disgust in disorders of food avoidance

Background Individuals with extreme food avoidance such as Avoidant Restrictive Food Intake Disorder (ARFID) experience impairing physical and mental health consequences from nutrition of insufficient variety or/and quantity. Identifying mechanisms contributing to food avoidance is essential to develop effective interventions. Anxiety figures prominently in theoretical models of food avoidance; however, there is limited evidence that repeated exposures to foods increases approach behavior in ARFID. Studying disgust, and relationships between disgust and anxiety, may offer novel insights, as disgust is functionally associated with avoidance of contamination from pathogens (as may occur via ingestion) and is largely resistant to extinction. Method This exploratory, cross-sectional study included data from 1,644 adults who completed an online questionnaire. Participant responses were used to measure ARFID classification, picky eating, sensory sensitivity, disgust, and anxiety. Structural equation modeling tested a measurement model of latent disgust and anxiety factors as measured by self-reported frequency of disgust and anxiety reactions. Mediational models were used to explore causal ordering. Results A latent disgust factor was more strongly related to severity of picky eating (B approximate to 0.4) and ARFID classification (B approximate to 0.6) than the latent anxiety factor (B approximate to 0.1). Disgust partially mediated the association between anxiety and picky eating and fully mediated the association between anxiety and ARFID. Models testing the reverse causal ordering demonstrated poorer fit. Findings suggest anxiety may be associated with food avoidance in part due to increased disgust. Conclusions Disgust may play a prominent role in food avoidance. Findings may inform novel approaches to treatment.