Highlights
– In a population-based survey of 4,002 adults, 42.6% screened positive for ≥1 disorder of gut–brain interaction (DGBI); ARFID-positive screens were more common in participants with DGBI (34.6%) than without (19.4%).
– ARFID symptom profiles among adults with DGBI most often reflected lack of interest in eating (21.5%) and sensory-based avoidance (18.1%), with fear of aversive consequence less common (9.9%).
– The likelihood of a positive ARFID screen rose with the number of affected DGBI anatomic regions (from 19.4% with no DGBI to 61.4% with four regions; P < .001).
– DGBI patients who screened positive for ARFID had higher prevalence of underweight, greater somatic and psychological symptom burden, poorer quality of life, and greater healthcare utilization than those with DGBI alone.
Background: why this matters
Disorders of gut–brain interaction (DGBI; formerly termed functional gastrointestinal disorders) are highly prevalent, heterogenous conditions characterized by chronic GI symptoms without structural explanations. Symptoms commonly affect eating behavior through pain, early satiety, nausea, dyspepsia, or bowel habit disturbance, and can alter appetite, meal timing, and food selection.
Avoidant/restrictive food intake disorder (ARFID) is an eating/feeding disturbance defined by restricted food intake leading to weight loss or nutritional deficiency, dependence on enteral feeding or supplements, and/or psychosocial impairment, without body image disturbance. ARFID presentations can include lack of interest in eating, sensory sensitivity to food, and fear of aversive consequences (e.g., choking or vomiting).
While specialist-clinic series have suggested overlap between DGBI and restrictive eating presentations, robust population-based data on the co-occurrence of ARFID symptoms and DGBI in adults have been lacking. That gap matters because coexisting ARFID-like behaviors may amplify malnutrition risk, psychological distress, and healthcare needs, and they require integrated clinical management across gastroenterology, nutrition, and mental health.
Study design
Flack et al. conducted an internet-based, cross-sectional population survey in the United Kingdom and the United States in 2023. Demographic quotas were predefined to approximate national distributions. The survey instruments included the Rome IV diagnostic questionnaire to classify DGBI, the Nine-Item ARFID Screen to identify ARFID symptom domains, and validated or commonly used measures capturing body mass index (self-reported), nongastrointestinal somatic symptoms, anxiety and depression, quality of life, and healthcare use.
Primary comparisons contrasted prevalence of positive ARFID screens between participants with and without DGBI, and secondary analyses examined ARFID subtypes, relationship to number of DGBI anatomic regions, nutritional status, symptom burden, psychological measures, quality of life, and healthcare utilization. Analyses adjusted for relevant covariates and reported odds ratios with 95% confidence intervals.
Key findings
Sample and prevalence: The final analytic sample comprised 4,002 adults (median age 46, range 18–91 years; 50% female). Overall, 1,704 participants (42.6%) met symptom criteria compatible with at least one DGBI using Rome IV criteria.
ARFID prevalence and association with DGBI
Positive ARFID screens were substantially more common in people with DGBI than in those without: 34.6% vs 19.4%. After adjustment for covariates, the association remained statistically significant (adjusted odds ratio 1.67; 95% CI 1.43–1.94). This pattern was consistent in both the UK and US subsamples.
ARFID symptom domains
When ARFID subdomains were examined among participants with DGBI, the most frequently reported symptom categories were lack of interest in eating (21.5%) and sensory-based avoidance (18.1%); fear of aversive consequences (for example fear of choking, vomiting) was reported less commonly (9.9%). These proportions indicate considerable heterogeneity in the nature of restrictive eating presentations co-occurring with DGBI.
Relationship to DGBI extent
A dose–response relationship emerged between extent of DGBI involvement (number of anatomic regions affected) and ARFID prevalence: 19.4% in those with no DGBI, 27.7% with DGBI in 1 region, 39.5% with 2 regions, 50.0% with 3 regions, and 61.4% with DGBI in 4 regions (P < .001). This gradient suggests cumulative symptom burden across GI domains increases the likelihood of clinically relevant restrictive eating behaviors.
Clinical burden and outcomes
Participants who had both DGBI and a positive ARFID screen had worse overall health-related outcomes compared with those with DGBI alone. Key differences included higher prevalence of underweight (7.9% vs 1.5%), greater nongastrointestinal somatic symptoms, higher levels of anxiety and depression, and reduced mental and physical quality of life. They also reported increased healthcare utilization, consistent with greater morbidity and complexity of care needs.
Interpretation and clinical implications
These findings, from a large population-based sample across two countries, indicate that ARFID-like symptoms are common in adults with DGBI and are associated with measurable excess clinical burden. For clinicians, there are several practical takeaways:
- Screening: Routine, brief screening for restrictive eating behavior and ARFID symptoms should be considered in patients with DGBI, particularly when symptoms are refractory, weight loss or nutrient deficiency is present, or when multiple GI regions are affected.
- Differential diagnosis: Clinicians should distinguish ARFID (a feeding/eating disorder) from adaptive restriction driven solely by transient symptoms. Key differentiators include severity (weight/nutritional consequences), duration, psychosocial impairment, and presence/absence of body image concerns.
- Multidisciplinary care: The convergence of GI symptom burden, nutritional compromise, and psychological distress argues for integrated care pathways involving gastroenterologists, dietitians experienced with disordered eating, and mental health professionals with expertise in ARFID and behavioral interventions.
- Triage and referral: Patients with documented underweight, rapid weight loss, severe micronutrient deficiency, or high psychological distress warrant expedited multidisciplinary assessment and possible medical and psychiatric intervention.
Mechanistic considerations
The observed co-occurrence is biologically and psychologically plausible. Chronic GI symptoms such as early satiety, nausea, pain, and postprandial distress can directly reduce appetite and food tolerance, foster avoidance learning (anticipation of aversive sensation), and increase hypervigilance to sensory properties of food. Conversely, longstanding restrictive eating can alter gut physiology, microbiota composition, and visceral sensitivity, potentially perpetuating DGBI symptoms—a bidirectional relationship that supports integrated treatment strategies.
Strengths
Salient strengths of the study include the large sample size, use of quota-sampling to approximate population demographics in two countries, standardized instruments (Rome IV and a short validated ARFID screen), and comprehensive assessment of clinical, psychological, and utilization outcomes. The dose–response relationship with number of affected DGBI regions strengthens the inference of a meaningful association.
Limitations
Important limitations temper conclusions. The cross-sectional, internet-survey design precludes causal inference and temporality—whether DGBI leads to ARFID symptoms, vice versa, or both result from shared vulnerability is unresolved. ARFID identification relied on a brief screening tool rather than full diagnostic interview; screens can overestimate prevalence compared with gold-standard psychiatric assessment. Self-reported height/weight and symptom reporting introduce measurement error. Internet panels may underrepresent some groups, and quota sampling does not fully ensure representativeness. Finally, the study abstract does not provide full details on response rates, nonresponse bias, or funding sources.
Research and practice gaps
Key areas for future work include longitudinal studies to define directionality and natural history, clinic-based validation of the Nine-Item ARFID Screen in DGBI populations, mechanistic studies linking gut physiology to restrictive eating phenotypes, and randomized trials testing integrated gastroenterology–psychology–nutrition interventions. Implementation research should evaluate efficient screening strategies in GI clinics and pathways for timely multidisciplinary referral.
Practical screening approach for clinicians
While formal guidance awaits further evidence, a pragmatic approach in GI practice could include:
- Asking brief screening questions about reduced appetite, selective avoidance of foods for sensory reasons, fear of choking/ vomiting leading to meal avoidance, and unplanned weight loss or need for supplements.
- Using a short validated screen (such as the Nine-Item ARFID Screen) when concerns arise, followed by referral for nutritional assessment and specialty mental health evaluation if the screen is positive and/or there is weight loss, malnutrition, or psychosocial impairment.
- Involving dietitians early to assess caloric adequacy, micronutrient status, and safe refeeding approaches when indicated.
- Referring for behavioral therapies targeting ARFID (for example, exposure-based approaches and family- or adult-focused behavioral treatments) in conjunction with medical management of underlying GI contributors.
Conclusion
Flack et al.’s population-based study highlights that ARFID symptoms are common among adults with DGBI and are associated with substantial additional clinical burden including underweight, greater psychological distress, worse quality of life, and increased healthcare use. The findings support routine screening for restrictive eating behaviors in patients with DGBI and prompt multidisciplinary management when ARFID features are identified. Longitudinal and intervention studies are needed to clarify causal pathways and to develop targeted integrated care models that address both gut–brain and feeding/eating dimensions.
Funding and trial registration
The published abstract did not report study funding or a clinicaltrials.gov registration number; readers should consult the full article for details.
Selected references
1. Flack R, Brownlow G, Burton-Murray H, Palsson O, Aziz I. The Prevalence and Burden of Avoidant/Restrictive Food Intake Disorder Symptoms in Adults With Disorders of Gut-Brain Interaction: A Population-Based Study. Gastroenterology. 2025 Sep 4. doi: 10.1053/j.gastro.2025.07.043. Epub ahead of print. PMID: 40914329.
2. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, VA: American Psychiatric Association; 2013. (DSM-5) — diagnostic criteria for ARFID.
3. Drossman DA, Hasler WL. Rome IV—functional GI disorders: disorders of gut–brain interaction. Gastroenterology. 2016;150(6):1257–1261. (Rome IV conceptual framework and diagnostic criteria)
Author note
This article was prepared by a clinical medical writer to interpret and contextualize the findings of Flack et al. for a clinician audience. The summary integrates study data reported in the cited Gastroenterology article and established diagnostic frameworks.