Characteristics and clinical applicability of five dietary interventions for irritable bowel syndrome: a Systematic review and Network meta-analysis

Background Dietary interventions are first-line management for irritable bowel syndrome (IBS), but their relative efficacy, acceptability, and safety remain incompletely understood. This systematic review and meta-analysis aimed to comprehensively evaluate five dietary interventions (LFD, MD/MED-LFD, TDA, SSRD, GFD) for adult IBS patients. Methods We searched PubMed, Embase, Cochrane Library, and Web of Science for RCTs published between 2019 and 2025 comparing dietary interventions for IBS. Meta-analyses were performed using a random-effects model, and risk of bias was assessed using the Cochrane RoB 2.0 tool. Results Ten RCTs involving 939 participants were included. Frequentist network meta-analysis demonstrated that all specific dietary interventions were significantly superior to habitual diet/control. Based on the P-score ranking matrix, the combined Mediterranean-low FODMAP diet (MED-LFD) had the highest probability of being the most effective intervention (P-score = 0.76), followed by the starch- and sucrose-reduced diet (SSRD, P-score = 0.70), Mediterranean diet alone (MD, P-score = 0.68), and LFD (P-score = 0.60). Traditional dietary advice (TDA) showed lower comparative efficacy (P-score = 0.20). Node-splitting analysis confirmed the robustness of the network model with no significant local inconsistency (P > 0.05 for all). Conclusion LFD, MED-LFD, TDA, SSRD, and GFD have distinct efficacy, acceptability, and safety profiles. LFD is a reliable first-line option, MED-LFD offers favorable long-term outcomes, TDA is acceptable but less effective, SSRD is a viable alternative to LFD, and GFD is only suitable for specific subgroups. Further research is needed to confirm long-term efficacy and identify subgroup responders.