Food avoidance and restriction in adults: a cross-sectional pilot study comparing patients from an immunology clinic to a general practice

Michael Fitzgerald, Brad Frankum

With the introduction of avoidant/restrictive food intake disorder (ARFID) in the Diagnostic and Statistical Manual - fifth edition, there is an increased need to understand the prevalence and pattern of food avoidance and restriction in adults. High rates of food allergy and intolerance in immunology clinic populations, and subsequent high rates of elimination diets, place these individuals at a greater risk of developing pathological eating behaviours. This descriptive cross sectional pilot study aims to provide preliminary data on the prevalence and nature of food avoidance and restriction in an adult population, and to explore the reasons for this behaviour. A self-administered questionnaire was designed and distributed to adults presenting to an immunology clinic and a general practice over the course of 6 months to describe the prevalence and nature of avoidant and restrictive eating behaviours in this population. Pearson's chi square test was used to examine the strength of a potential link to a formal diagnosis of avoidant restrictive food intake disorder in these patients. A total of 102 completed questionnaires were used for data analysis. Food avoidance or restriction was detected in 81 respondents (79%), with rates not significantly higher in the immunology clinic group compared to the general practice group (p = .242). Food allergy and intolerance were the most common reasons for disturbed eating patterns. Life impact secondary to food avoidance and restriction was reported by 26% of respondents, with significantly higher rates observed in the immunology clinic cohort compared to the general practice (p = .011). Eating disturbances similar to those characteristic of ARFID are very common in adults. Food avoidance and restriction due to perceived food allergy and intolerance are significant reasons for such disordered eating patterns, particularly in an immunology clinic population. Further investigation is needed to determine if such eating behaviours are pathological and whether they qualify for a diagnosis of ARFID.