Background: Ultra-processed foods (UPFs) may lead to dysbiosis of gut microbiota, which significantly contributes to the development of disorders of gut-brain interaction (DGBI). However, knowledge regarding the association of UPFs with DGBI is scarce. Therefore, we aimed to evaluate the association of UPFs with DGBI and its common subtypes in Iranian adults.
Methods: In this cross-sectional study, a total of 1892 adults were included. Dietary intake of participants was evaluated using a validated version of a dish-based food frequency questionnaire, and UPFs were defined using the NOVA system classification. DGBI, including heartburn, functional dyspepsia (FD), and irritable bowel syndrome (IBS), were examined using the ROME IV questionnaire. The odds of suffering from any DGBI and its subtypes across the tertiles of UPFs were assessed using logistic regression.
Results: After controlling for potential confounders, being in the highest versus lowest tertile of UPFs consumption was associated with increased risk of DGBI (OR = 1.62; 95% CI: 1.20, 2.17) and IBS (OR = 1.89; 95% CI: 1.01, 3.55). However, UPFs consumption was not significantly associated with odds of FD and heartburn in the fully adjusted model. In stratified analysis by sex, females in the highest tertile of UPFs consumption had higher risks of DGBI, IBS, and FD than those in the lowest tertile. In males, in the fully adjusted model, no significant association was found between UPFs consumption and risk of DGBI and its subtypes.
Conclusion: Higher consumption of UPFs was significantly associated with an increased risk of total DGBI and IBS in Iranian adults. However, considering the limitations of the available evidence regarding processed foods and DGBI, further large-scale prospective studies are needed to provide more data.
Keywords: disorder of gut–brain interaction; functional dyspepsia; functional gastrointestinal disorders; heartburn; irritable bowel syndrome; processed food; ultra‐processed foods.
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