Skip to content

The Low FODMAP Diet in Individuals With Small Intestinal Bacterial Overgrowth (SIBO)

Assessment of the Impact of the Low FODMAP Diet on Gastrointestinal Symptoms and Nutritional Status in People With Small Intestinal Bacterial Overgrowth (SIBO)

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07424313
Enrollment
51
Registered
2026-02-20
Start date
2024-02-08
Completion date
2026-01-15
Last updated
2026-02-24

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

Conditions

SIBO, Small Intestinal Bacterial Overgrowth, Small Intestinal Bacterial Overgrowth Syndrome (SIBO)

Brief summary

This study aims to assess the impact of a low FODMAP diet (LFD) on gastrointestinal symptoms and nutritional status in individuals diagnosed with small intestinal bacterial overgrowth (SIBO). Participants were randomly assigned to either an intervention group or a control group following completion of antibiotic therapy. The intervention group followed a LFD, while the control group followed a normal diet, in accordance with the principles of rational nutrition. Gastrointestinal symptoms, nutritional status, and quality of life were assessed using questionnaires, dietary records, anthropometric measurements, and blood biochemical parameters.

Interventions

OTHERLow FODMAP Diet

Following a low FODMAP diet (elimination and reintroduction phases for 4 and 8 weeks, respectively, for a total of 12 weeks)

OTHERHealthy Eating Diet

Applying recommendations consistent with proper nutrition principles, with particular focus on breaks between meals and the principle of mindful eating

Sponsors

Warsaw University of Life Sciences
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* age \> 18 years, * SIBO diagnosed by a doctor based on a hydrogen and methane breath test, * the use of one type of antibiotic at the same dose and for the same period of time.

Exclusion criteria

* BMI \< 18.5 kg/m2, * pregnancy and breastfeeding, * the occurrence of allergies and food intolerances, * previous operations on the digestive tract (except appendectomy and hemorrhoidectomy), * eating disorders, * inflammatory bowel diseases, * celiac disease, * cancer, heart, liver and lung diseases with severe course, as well as neurological or psychiatric diseases, * use of dietary modifications in the last 3 months, * use of antibiotics other than those prescribed by a doctor to treat SIBO in the last 3 months, * implanted stimulators (limitation of body composition measurement)

Design outcomes

Primary

MeasureTime frameDescription
Gastrointestinal Adverse Symptoms Assessment Questionnaire (GASAQ) total score12 weeksChange in gastrointestinal symptom severity assessed using the Gastrointestinal Adverse Symptoms Assessment Questionnaire (GASAQ). The total score ranges from 0 to 100 points, with higher scores indicating more severe gastrointestinal symptoms. Assessments were performed at baseline and after the dietary intervention.
Nutritional status - Mini Nutritional Assessment (MNA)12 weeksChange in nutritional status assessed using the Mini Nutritional Assessment (MNA) questionnaire. The total score ranges from 0 to 30 points, with higher scores indicating better nutritional status. Assessments were performed at baseline and after the dietary intervention.
Nutritional status - Blood biochemical parameters (Serum vitamin D concentration)12 weeksChange in serum vitamin D levels measured in ng/mL at baseline and after the dietary intervention.
Nutritional status - Blood biochemical parameters (Serum folate concentration)12 weeksChange in serum folate levels measured in ng/mL at baseline and after the dietary intervention.
Nutritional status - Blood biochemical parameters (Iron status parameters)12 weeksChange in serum iron concentration (µg/dL) measured at baseline and after the dietary intervention.
Nutritional status - Blood biochemical parameters (Serum albumin concentration)12 weeksChange in serum albumin levels measured in g/L at baseline and after the dietary intervention.
Nutritional status - Anthropometric parameters (body weight)12 weeksChange in body weight (kg) measurements at baseline and after the dietary intervention.
Nutritional status - Anthropometric parameters (body mass index (BMI)12 weeksChange in BMI (kg/m²) at baseline and after the dietary intervention. BMI calculated from measured body weight and height (kg/m²).
Nutritional status - anthropometric parameters (body fat percentage)12 weeksChange in body fat percentage (%) at baseline and after the dietary intervention. Body fat percentage measured using bioelectrical impedance analysis (ACCUNIQ BC720).

Secondary

MeasureTime frameDescription
Quality of life - IBS-specific (Irritable Bowel Syndrome-Quality of Life (IBS-QOL) total score)12 weeksChange in quality of life assessed using the Irritable Bowel Syndrome-Quality of Life (IBS-QOL) questionnaire. Scores range from 0 to 100 points, with higher scores indicating better quality of life. Assessments were performed at baseline and after the dietary intervention.
Quality of Life - General (Short Form-36 Health Survey (SF-36) total score)12 weeksChange in general quality of life assessed using the Short Form-36 Health Survey (SF-36), Polish version. Scores range from 0 to 100 points, with higher scores indicating better perceived health status. Assessments were performed at baseline and after the dietary intervention.

Countries

Poland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 25, 2026