Impacts of the Long‐Term Low‐FODMAP Diet in Patients With Irritable Bowel Syndrome: A Systematic Review and Meta‐Analysis

Background and Objectives The low fermentable oligo‐, di‐, monosaccharides and polyols diet (LFD) is the primary intervention for managing irritable bowel syndrome (IBS). However, due to its restrictive nature, concerns have been raised about its safety and efficacy with long‐term use. This study aims to investigate the outcomes of long‐term LFD (LLFD) in patients with IBS. Methods A systematic search was performed in PubMed, Embase and Scopus up to November 2024. LLFD was defined as LFD for at least 6 months. A random‐effects model was applied to estimate the standardised mean difference (SMD) and 95% confidence interval (95% CI) for each outcome. The protocol of the study was registered in PROSPERO (ID CRD42024609338). Results Of the total 2724 screened records, five studies finally met the inclusion criteria and were included in the study (324 patients). LLFD was able to reduce overall gastrointestinal symptoms (SMD −1.97, 95% CI −3.63 to −0.30), anxiety (SMD −0.40, 95% CI −0.65 to −0.15) and depression (SMD −0.28, 95% CI −0.53, to −0.03). Additionally, LLFD improved quality of life (mean difference 0.53, 95% CI 0.24–0.83). However, it was not able to improve the quality of sleep (SMD −0.13, 95% CI −0.39 to 0.12). Conclusions The long‐term use of LFD appears effective in improving gastrointestinal symptoms, psychological well‐being, and quality of life in patients with IBS. Further research is needed to confirm these findings and explore additional long‐term outcomes.