N/A
N=29
Dietary Triggers of Gastrointestinal Symptoms in IBS Patients
Irritable Bowel Syndrome
Bottom Line
View on ClinicalTrials.gov: NCT03664531 ↗Enrolled (actual)
29
Serious AEs
0.6%
Results posted
Apr 2026
Primary outcome: Primary: Number of Participants With Worsening Irritable Bowel Syndrome (IBS) Symptoms Based on IBS-SSS — 8; 10; 11 Participants
Study Design & Population
- Study type
- Interventional
- Phase
- N/A
- Interventions
- Purified gluten (Other); Non-purified gluten (containing ATIs) (Other); Sham (Other)
- Age
- Adult, Older Adult · 18+ yrs
- Sex
- All
- Sponsor
- McMaster University
- Primary completion
- Apr 2022
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Number of Participants With Worsening Irritable Bowel Syndrome (IBS) Symptoms Based on IBS-SSS |
8; 10; 11 | — |
| SECONDARY General Gastrointestinal Symptoms |
58.7; 57.0; 59.5; 58.6; 60.7; 59.9 | — |
| SECONDARY Orocecal Transit |
5.0; 7.0; 12.0 | — |
| SECONDARY Anti-gliadin Antibody (AGA) Levels |
2; 26 | — |
| SECONDARY Gut Microbiota Profiles |
— | — |
| SECONDARY Genetic Predisposition for Celiac Disease |
6; 2; 2; 8; 2; 5 | — |
| SECONDARY Depression, Anxiety and Stress |
2.0; 3.0; 2.0; 3.0; 2.0; 2.0 | — |
| SECONDARY Somatic Symptoms |
8.0; 7.5; 6.0 | — |
| SECONDARY Stool Consistency |
3.0; 4.5; 3.0 | — |
| SECONDARY Gluten Levels in Stool |
0.10; 0.43; 0.57 | — |
| SECONDARY Diet Assessment |
— | — |
| SECONDARY IBS Symptom Duration |
150.5; 145.6; 149.3; 185.4; 179.5; 177.8 | — |
| SECONDARY Systemic Immune Reactivity |
— | — |
| SECONDARY Long-term Gluten-free Diet Adherence |
5; 4; 2; 3; 6; 4 | — |
| SECONDARY Psychological and Gastrointestinal Symptoms After Learning Diet Triggers and Genetic Results (Unblinding Participants to Diet Triggers During Post-study Follow-up) |
176.5; 163.4; 57.4; 55.9; 53.5; 52.8 | — |
| SECONDARY Irritable Bowel Syndrome (IBS) Symptoms (Continuous) |
166.0; 166.5; 179.5 | — |
Summary
This crossover randomized controlled trial will evaluate the effects of purified gluten and whole wheat (gluten combined with amylase-trypsin inhibitors (ATIs)) on inducing intestinal and extra-intestinal symptoms in irritable bowel syndrome (IBS) patients. All participants will be put on a gluten-free diet and then challenged with muesli bars containing either purified gluten, whole wheat (gluten with ATIs), or gluten-free sham.
Eligibility Criteria
Inclusion Criteria
- IBS diagnosis based on Rome IV criteria.
- Previously improved while on a gluten-free diet.
- Compliance with the study procedures (according to the investigator's own judgement).
- Signing the Study Informed Consent form.
Exclusion Criteria
- Concurrent systemic disease and/or laboratory abnormalities considered by investigators to be risky or that could interfere with data collection.
- Concurrent organic gastrointestinal disease (i.e. Celiac disease, Inflammatory Bowel Disease, peptic ulcer disease, etc.) other than benign polyps, diverticulosis, hemorrhoids, lipoma and melanosis coli.
- Major abdominal surgery with the exception of hernia repair, appendectomy, Caesarian section, tubal ligation, cholecystectomy, hysterectomy, and hemorrhoidectomy.
- History of active cancer in the last 5 years, other than skin basal cells cancer.
- Pregnant or breastfeeding women.
- Current use of antibiotics or antibiotic treatment within 1 months before the first visit.
- Consumption of probiotics within 1 month prior to the first visit.
- Use of non-authorized medications (see Unauthorized Medications section).
- Patients on a high fibre diet (>35 g/day for males, > 25 g/day for females), consuming high inulin containing foods (>5 g/day), and/or consuming dietary fibre supplements (as assessed by dietary assessment questionnaire) in the 4 weeks prior to the first visit.
- Patients currently participating or having participated in a trial within the past month.
Data sourced from ClinicalTrials.gov (NCT03664531). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.