Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
Colorectal Research Center, Iran University of Medical Sciences, Tehran, Iran.
Food Funct. 2024 May 20;15(10):5195-5208. doi: 10.1039/d3fo03717g.
A low FODMAP diet (LFD) is a common restrictive diet to manage the symptoms of irritable bowel syndrome (IBS). However, there is no consensus on the alleviating effects of this diet. Herein, a systematic umbrella review with meta-analysis was conducted to investigate the effect of an LFD on IBS symptoms and its secondary outcomes in patients, which were not reported in previous meta-analyses. We performed a systematic literature search in PubMed, Scopus, and ISI Web of Science up to December 2023. The methodological quality of systematic reviews and their included trials was evaluated using AMSTAR 2 and the Cochrane risk of bias, respectively. The certainty of the evidence tool was evaluated using the GRADE approach. The data related to IBS symptoms, quality of life (QoL), microbiome diversity, and stool short-chain fatty acids were extracted. A random-effect (if RCTs ≥ 6) or fixed-effect model (if RCTs < 5) was used to recalculate effect sizes and 95% CIs and report them in both qualitative and quantitative terms (pooled risk ratio, Hedges' , and weighted mean difference). A total of 658 articles were initially identified, with 11 meta-analyses and 24 RCTs reporting 28 outcomes with 1646 participants included. An LFD significantly affected the clinical improvement of total symptoms according to the IBS-SSS questionnaire (RR: 1.42; 95% CI: 1.02, 1.97; = 0.04) in all the subtypes of IBS and also had favorable effects on stool consistency (WMD: -0.48; 95% CI: -0.902, -0.07) and frequency (WMD: -0.36; 95% CI: -0.61, -0.10) and some other GI symptoms in both less and more than 4 weeks of diet intervention except for stool consistency, which needed more than 4 weeks of LFD implementation. A significant QoL improvement was observed but not in the anxiety and depression state. Furthermore, some studies showed that an LFD may increase fecal pH and dysbiosis and reduce SCFA and the abundance of . In conclusion, an LFD can alleviate symptoms and QoL in IBS patients, although dysbiosis may occur. Considering the low certainty of evidence, strong RCTs with more appropriate designs are needed.
低 FODMAP 饮食（LFD）是一种常见的限制饮食，用于缓解肠易激综合征（IBS）的症状。然而，这种饮食的缓解效果尚无共识。在此，我们进行了一项系统的伞式综述和荟萃分析，以调查 LFD 对 IBS 症状及其在患者中的次要结局的影响，这在以前的荟萃分析中并未报道。我们在 PubMed、Scopus 和 ISI Web of Science 上进行了系统的文献检索，截至 2023 年 12 月。使用 AMSTAR 2 和 Cochrane 偏倚风险分别评估系统评价及其纳入试验的方法学质量。使用 GRADE 方法评估证据的确定性工具。提取与 IBS 症状、生活质量（QoL）、微生物组多样性和粪便短链脂肪酸相关的数据。使用随机效应（如果 RCT 数≥6）或固定效应模型（如果 RCT 数<5）重新计算效应大小和 95%置信区间，并以定性和定量方式报告（汇总风险比、Hedges'g 和加权均数差）。最初共确定了 658 篇文章，其中 11 项荟萃分析和 24 项 RCT 报告了 28 项结局，共有 1646 名参与者。LFD 显著影响 IBS-SSS 问卷评估的所有 IBS 亚型的总症状临床改善（RR：1.42；95%CI：1.02，1.97； = 0.04），并且对粪便稠度（WMD：-0.48；95%CI：-0.902，-0.07）和频率（WMD：-0.36；95%CI：-0.61，-0.10）也有有利影响，除了需要超过 4 周的 LFD 实施才能改善粪便稠度外，在饮食干预少于 4 周和超过 4 周时对其他一些胃肠道症状也有改善。观察到 QoL 显著改善，但焦虑和抑郁状态没有改善。此外，一些研究表明，LFD 可能会增加粪便 pH 值和失调，并减少 SCFA 和 abundance of. 综上所述，LFD 可以缓解 IBS 患者的症状和生活质量，尽管可能会发生失调。考虑到证据的确定性较低，需要进行具有更合适设计的强有力的 RCT。
