Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: A meta-analysis of clinical studies

Abstract

BackgroundIrritable bowel syndrome (IBS) and functional digestive tract disorders, e.g. functional bloating, carbohydrate maldigestion and intolerances, are very common disorders frequently causing significant symptoms that challenge health care systems. A low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) diet is one of the possible therapeutic approaches for decreasing abdominal symptoms and improving quality of life.ObjectivesWe aimed to meta-analyze data on the therapeutic effect of a low-FODMAP diet on symptoms of IBS and quality of life and compare its effectiveness to a regular, standard IBS diet with high FODMAP content, using a common scoring system, the IBS Symptom Severity Score (IBS-SSS).MethodsA systematic literature search was conducted in PubMed, EMBASE and the Cochrane Library as well as in the references in a recent meta-analysis. Adult patients diagnosed with IBS according to the Rome II, Rome III, Rome IV or NICE criteria were included in the analysis.Statistical methodsMean differences with 95% confidence intervals were calculated from studies that contained means, standard deviation (SD) or mean differences and SD of differences and p-values. A random effect model was used because of the heterogeneity (Q test (χ2) and I2 indicator). A p-value of less than 0.05 was chosen to indicate a significant difference.ResultsThe literature search yielded 902 publications, but only 10 were eligible for our meta-analysis. Both regular and low-FODMAP diets proved to be effective in IBS, but post-diet IBS-SSS values were significantly lower (p = 0.002) in the low-FODMAP group. The low-FODMAP diet showed a correlation with the improvement of general symptoms (by IBS-SSS) in patients with IBS.ConclusionsThis meta-analysis provides high-grade evidence of an improved general symptom score among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet, therefore showing its superiority to regular IBS dietary therapy. These data suggest that a low-FODMAP diet with dietitian control can be a candidate for first-line therapeutic modality in IBS. Because of a lack of data, well-planned randomized controlled studies are needed to ascertain the correlation between improvement of separate key IBS symptoms and the effect of a low-FODMAP diet.

Neither self‐reported atopy nor IgE‐mediated allergy are linked to gastrointestinal symptoms in patients with irritable bowel syndrome

“…Another possible explanation of the discrepancy between having self‐perceived food intolerance and food allergy could be the findings of an intestinal IgE‐mediated response in patients with food‐related gastrointestinal symptoms, without increased levels of IgE in peripheral blood . Also, the role of fermentable carbohydrates (fermentable oligosaccharides, disaccharides, monosaccharides and polyols: FODMAPs) for IBS symptom generation has been frequently discussed recently . These represent carbohydrates that are not fully absorbed in the small intestine, but will rather act as substrates to the gut microbiota in the colon, causing excessive gas production and water retention.…”

Dietary therapies for functional bowel symptoms: Recent advances, challenges, and future directions

“…The range of dietary therapies available creates the issue of choosing which therapy to trial in the individual and if unsuccessful, whether another dietary therapy may be worthwhile. The National Institute for Clinical Excellence (NICE) guidelines are considered as first‐line therapy by the British Dietetic Association, although some have argued that the low FODMAP diet should now be considered as a first line . Variations in recommendations exist between countries, partially related to access to suitably trained dietitians .…”

Randomised clinical trial: pregabalin vs placebo for irritable bowel syndrome

“…Antispasmodics as well as tricyclic antidepressants as neuromodulators are frequently utilised. Newer IBS therapies such as linaclotide, eluxadoline and a low FODMAP diet are also available . However, these therapies are not effective for all patients, and patients and providers then struggle to improve pain without resorting to addictive therapies such as opioid drugs, which should almost never be prescribed for IBS pain …”