Response to Dietary Interventions for Irritable Bowel Syndrome Correlates With Changes in Serum and Urine Metabolites

Fodmap diet concept. Low fodmap ingredients – poultry meat, fish, seafood, vegetables and fruits and words Fodmap in center, on dark background. Top view or flat lay.
Researchers investigated serum and urinary metabolite patterns as a result of certain dietary interventions in patients with irritable bowel syndrome.

Patients with irritable bowel syndrome (IBS) who were responders to a low fermentable oligo-, di-, monosaccharide and polyol (FODMAP) diet exhibited distinct metabolite patterns compared with nonresponders. These findings were published in PLoS One.

Adults (N=56) with IBS were recruited from 2 cities in Sweden between 2013 and 2014. Patients were randomly assigned to receive a 4-week low FODMAP diet (LFD; n=28) or traditional IBS diet (TID; n=28) intervention. The outcomes were pre- and post-intervention fasting serum and urine metabolite concentrations.

The LFD and TID cohorts were aged mean 47.1 (range, 21-69) years and 41.6 (range, 18-68) years, the women:men ratio was 23:5 and 23:5, body mass index (BMI) was 24.8 (range, 19.8-35.5) kg/m2 and 23.7 (range, 19.7-31.2) kg/m2, and the IBS Severity Scoring System indicated severe disease among 67.9% and 50%, respectively.

There were 15 responders to the LFD and 14 to the TID. Metabolite patterns were significantly correlated with age for serum (P =.0006) and urine (P =.0004) samples and BMI was correlated with serum metabolite patterns (P =.007).

A 5-component model best fit the changes in metabolites with regard to treatment and response (R2X, 0.58; Q2X, 0.447; Q2Y, 0.941). Responders to the LFD had a significant reduction in serum glucose and urine pantothenate and an increase in serum 2-hydroxybyturate and an unknown urine metabolite. Responders to the TID exhibited a larger diversity in metabolites compared with LFD.

After correcting for confounders, responders and nonresponders to the LFD differed significantly for glucose (P =.049) and pantothenate (P =.048).

Researchers note this study was an analysis of previously published data and should be regarded as a hypothesis generating, exploratory analysis.

The study authors concluded that responders and nonresponders to an LFD for the treatment of IBS exhibited differing patterns of metabolite changes. Additional studies are needed to better understand the mechanism of response to dietary modification in the IBS setting.


Nybacka S, Simrén M, Störsrud S, Törnblom, Winkvist A, Lindqvist HM. Changes in serum and urinary metabolomic profile after a dietary intervention in patients with irritable bowel syndrome. PLoS One. 2021;16(10):e0257331. doi:10.1371/journal.pone.0257331