Eating disorders encompass a range of behavioral conditions characterized by profound and persistent disruptions in eating habits, accompanied by distressing thoughts and emotions.¹ These conditions, which are potentially life-threatening and significantly affect quality of life, have increased over the past 20 years.¹ They include anorexia nervosa, bulimia nervosa, binge eating disorder (BED), and avoidant restrictive food intake disorder. Notably, individuals with eating disorders are more likely to experience meal-related dyspeptic symptoms and have a higher prevalence of functional dyspepsia (FD).^2,3 Among eating disorders, BED could be particularly associated with FD due to episodes of overeating accompanied by a loss of control; however, this connection has not been widely recognized. In this issue of the Journal of Neurogastroenterology and Motility, the study by Félix-Téllez et al⁴ highlights this intersection between BED and FD. This cross-sectional study, involving 1016 subjects, revealed an alarmingly high prevalence of FD in individuals with BED, reaching 53.6% in Mexico. Although the proportions of epigastric pain syndrome and postprandial distress syndrome were similar between individuals with and without BED, the overlap of these syndromes was higher in those with BED (24.5%) compared to those without BED (17.4%). This finding suggests that the presence of BED is associated with more complex pathophysiological mechanisms and symptom phenotypes.

However, this finding should be interpreted cautiously, as the prevalence of FD in individuals without BED was 43.8%, considerably higher than previously reported rates.⁵ Furthermore, the prevalence of BED was also higher compared to earlier studies, even when stricter DSM criteria (DSM-V) were applied.⁶ Nevertheless, this study underscores the importance of assessing eating habits when diagnosing FD.

Interestingly, early satiation was the most common symptom affecting 38.6% of the patients with BED. At first glance, this finding seems contradictory, given that BED is characterized by recurrent episodes of binge eating. Moreover, gastric capacity may increase in patients with BED, which in turn reduces satiety signals arising from gastric and post-gastric cues.⁷ However, patients with BED do not engage in binge eating at all times. According to the DSM-V, a binge-eating episode is defined as “Eating, in a discrete period of time (eg, within any 2-hour period), an amount of food that is definitely larger than most people would eat in a similar period of time under similar circumstances.”⁸ The frequency of binge eating varies from mild (1-3 episodes per week) to extreme (14 or more episodes per week).⁸ Therefore, if patients with BED experience early satiation, it likely occurs during periods when they are not engaging in binge eating. The study by Félix-Téllez et al⁴ did not specifically address this eating period context. Future research on BED and FD should differentiate between periods of binge eating and non-binge eating to clarify these findings.

During binge-eating episodes, patients often consume large quantities of food even when not physically hungry, eat more rapidly than normal, and continue eating until they feel uncomfortably full.⁹ In line with early satiation, fullness arising from excessive food intake cannot be considered as an FD symptom. Only fullness experienced during the non-binge eating period should be considered an FD symptom.

In this context, it is noteworthy that the Rome criteria define symptoms somewhat vaguely, lacking quantitative criteria or specific thresholds for the amount of food consumed for FD symptoms.^3,10 For example, postprandial fullness is described as “An unpleasant sensation like the prolonged persistence of food in the stomach.”¹⁰ This non-specific definition may fail to capture the nuanced experiences of BED patients, potentially leading to misclassification and diagnostic confusion. This ambiguity in the Rome criteria poses challenges for both clinicians and researchers, even when evaluating FD patients without eating disorders. Although pictogram-based tools have been developed to enhance symptom description, significant gaps remain.³ Diagnosing FD becomes even more complex when symptoms overlap with eating disorders. While the Rome IV criteria identify organic, systemic, or metabolic disorders as secondary causes of FD, they provide limited guidance on evaluating and integrating eating disorders into the diagnostic process of FD.

Ultimately, the limitations of symptom evaluation identified in Félix-Téllez et al^’s⁴ study emphasized the importance of assessing eating habits, particularly BED, in patients presenting with FD symptoms. In addition, this study challenges existing diagnostic paradigms and highlights the need for clearer definitions and more specific criteria in the upcoming Rome V criteria. Developing new subcategories or classification systems to capture the intersection between FD and eating disorders could facilitate a more nuanced understanding of these complex overlapping conditions. We hope future studies similar to Félix-Téllez et al⁴ will provide evidence supporting revisions to the Rome criteria, leading to better clinical practice.

This work was supported by Wonkwang University 2024 (C.S.C.).

None.

Yong Sung Kim: conceived and designed the study, and wrote the manuscript; Suck Chei Choi: conceived and designed the study; and Sung Hoon Yoon: critically revised the manuscript. All authors approved the final version of the manuscript.