The effect of a low FODMAP diet on luminal microbiota, fermentation and symptoms

The effect of a low FODMAP diet on luminal microbiota, fermentation and symptoms: A randomised controlled trial

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN62040425

Enrollment

Registered

2010-03-08

Start date

2010-02-01

Completion date

Unknown

Last updated

2015-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Irritable bowel syndrome Digestive System Irritable bowel syndrome

Interventions

4-week low FODMAP diet compared to usual diet. Patients in the intervention group will receive individualised dietary advice. A low FODMAP diet is a diet low in poorly absorbed fermentable carbohydra

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Patients will be recruited from Gastrointestinal and Dietetic Outpatient clinics at Guy?s and St Thomas? NHS Foundation Trust, London, UK. 1. Adult patients aged 18-65 years 2. Identified as having IBS based on Rome III criteria 3. Symptoms including bloating and/or diarrhoea

Exclusion criteria

Exclusion criteria: 1. Patients with any other gastrointestinal disease or gastrointestinal surgery 2. Patients whose major IBS symptom is constipation 3. Patients receiving lactulose or any other probiotic or prebiotic substances in the four weeks prior to the study 4. Patients who have taken antibiotics in the 4 weeks prior to the study 5. Patients who have received bowel preparation for investigative procedures in the 4 weeks prior to the study 6. Patients with any other significant major organ disorders, including diabetes, psychiatric and current eating disorders 7. Patients who report to be pregnant or lactating 8. Patients who have had changes to IBS medications or dose in the 4 weeks prior to the study

Design outcomes

Primary

Measure	Time frame
To assess the effect of a low FODMAP diet on faecal microbiota in patients with IBS. Faecal samples will be collected at baseline and at 4 weeks.	—

Secondary

Measure	Time frame
1. To assess the effect of a low FODMAP diet on faecal Short Chain Fatty Acid (SCFA), pH and faecal water in patients with IBS. 2. To assess the effect of a low FODMAP diet on symptoms in patients with IBS. 3. To assess the effect of a low FODMAP diet on stool consistency and frequency in patients with IBS. 4. To assess the nutritional adequacy of a low FODMAP diet in patients with IBS. 5. To assess the acceptability of a low FODMAP diet in IBS patients. 6. Weight and height. Outcomes will be assessed at baseline and at 4 weeks. Patients will keep a symptom diary and diet diary, and 2 questionnaires will be used to assess nutritional adequacy, FODMAP intake and diet acceptability.	—

Measure

Time frame

1. To assess the effect of a low FODMAP diet on faecal Short Chain Fatty Acid (SCFA), pH and faecal water in patients with IBS. 2. To assess the effect of a low FODMAP diet on symptoms in patients with IBS. 3. To assess the effect of a low FODMAP diet on stool consistency and frequency in patients with IBS. 4. To assess the nutritional adequacy of a low FODMAP diet in patients with IBS. 5. To assess the acceptability of a low FODMAP diet in IBS patients. 6. Weight and height. Outcomes will be assessed at baseline and at 4 weeks. Patients will keep a symptom diary and diet diary, and 2 questionnaires will be used to assess nutritional adequacy, FODMAP intake and diet acceptability.

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Countries

United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026