New evidence supports Mediterranean low-FODMAP diet for non-constipated IBS :- Medznat

Around 20% of irritable bowel syndrome (IBS) sufferers report that food intake triggers or worsens their symptoms.

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Key take away

In patients with non-constipated irritable bowel syndrome, a Mediterranean low-FODMAP diet provides greater and more sustained symptom relief, quality-of-life improvement, and treatment adherence than NICE dietary advice

Background

Around 20% of irritable bowel syndrome (IBS) sufferers report that food intake triggers or worsens their symptoms. Although a low-Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols (FODMAP) diet is an established dietary strategy for symptom management, evidence on Mediterranean-style low-FODMAP approaches remains limited.

This study scrutinized the potency of a Mediterranean low-FODMAP diet (MED-LFD) with dietary recommendations based on National Institute for Health and Care Excellence (NICE) guidelines and explored changes in stool volatile compounds as potential objective markers of treatment response.

Method

In this randomized controlled trial, 108 adults (aged 18–65 years) with Rome IV-defined IBS without constipation were randomly assigned to either the MED-LFD group or the NICE dietary advice group. The primary outcomes were changes in IBS symptom severity and responder rates, defined as a reduction of more than 50 points on the IBS Symptom Severity Score (IBS-SSS), assessed after the intervention and at 6 months. Secondary outcomes included quality of life, symptom burden, adequate symptom relief, anxiety and depression scores, and dietary adherence. Stool volatile compounds were analyzed via gas chromatography–mass spectrometry.

Result

The MED-LFD group attained greater improvements in symptom severity than the NICE group at both follow-up assessments. Responder rates and dietary adherence were also consistently higher among those receiving the Mediterranean low-FODMAP diet (Table 1)

All secondary outcomes, including quality of life, symptom burden, adequate relief, and psychological measures, showed similar benefits for the MED-LFD group. No serious adverse events were reported. Multivariable analysis identified the MED-LFD intervention as the strongest independent predictor of treatment response:

First follow-up: Odds ratio 6.66 (95% confidence interval, 1.46–30.4)
Second follow-up: Odds ratio 4.85 (95% confidence interval, 1.31–17.96)

Analysis of stool metabolites illustrated significant reductions in short-chain and branched-chain fatty acids at both follow-up assessments.

Conclusion

The Mediterranean low-FODMAP diet proved more effective than NICE dietary recommendations for improving symptoms, quality of life, and treatment adherence in patients with non-constipated IBS. While reductions in stool volatile compounds were noted, further research is needed to determine whether these changes can serve as reliable objective biomarkers of response to dietary interventions.