Meta-analysisindependent cross-checkabstract checked★ key study I-GUT-102 in-depth review
Which diets help irritable bowel syndrome
Efficacy of dietary interventions in irritable bowel syndrome: a systematic review and network meta-analysis.
Overview
Cuffe MS et al.. Lancet Gastroenterol Hepatol 2025 · PMID 40258374 · DOI 10.1016/S2468-1253(25)00054-8
A review of 28 trials found that several diets, especially low-FODMAP and a starch- and sugar-reduced diet, improved IBS symptoms more often than usual eating.
Does the study support the specific claim? Partly · Methodological quality: high
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Compare diets for IBS.
- How was the study done?
Network meta-analysis of randomised trials.
- How many people, animals or samples were studied?
28 trials, 2338 patients.
- What was actually found?
Low FODMAP and starch/sucrose-reduced diets improved global symptoms; only low FODMAP improved bloating.
- How large was the observed effect?
Non-improvement RR 0.41 (starch/sucrose-reduced) and 0.51 (low FODMAP).
- What do the results mean in everyday life?
Changing diet can help many but not all people with IBS.
- What are the study's limitations?
Diet trials hard to blind; few trials for some diets.
- What does it say about Elawady's specific claim?
Supports that diet matters; does not support an 85% cure.
- Do the results apply to Germany and Europe?
Applies to European patients.
- What can explicitly not be concluded from this study?
Cannot show that bread removal alone cures IBS.
Scientific in-depth review
1. Full reference
- Authors
- Cuffe MS et al.
- Journal
- Lancet Gastroenterol Hepatol
- Year
- 2025
- Identifier
- PMID 40258374 DOI 10.1016/S2468-1253(25)00054-8
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
No competing interests declared; no funding
2. Research question
What is the relative efficacy of dietary interventions requiring changes to more than one food in IBS?
3. Study design and population
- Study design
- Meta-analysis – Systematic review and network meta-analysis of randomised controlled trials of dietary interventions in IBS
- Population
Adults with IBS in 28 RCTs (2338 patients)
- Country
International
- Period
Search to 7 Feb 2025
- Sample size
28 RCTs; 2338 patients
- Inclusion and exclusion criteria
RCTs comparing an active diet with habitual diet, sham diet, high-FODMAP diet, other advice or another diet
4. Methods and endpoints
- Exposure / intervention
11 diets incl. low FODMAP, BDA/NICE advice, starch- and sucrose-reduced diet, lactose-reduced, Mediterranean, personalised
- Comparator
Habitual diet and other control diets
- Endpoints
Global IBS symptoms; abdominal pain; bloating/distension; bowel habit
- Statistical methods
Random-effects frequentist NMA; RR of symptoms not improving; P-scores; GRADE-type confidence ratings
5. Actual results
- Results
Global symptoms vs habitual diet: starch-reduced and sucrose-reduced diet RR 0.41 (0.26-0.67; 2 trials); low FODMAP RR 0.51 (0.37-0.70; 24 trials); BDA/NICE RR 0.62 (0.43-0.90; 8 trials). Bloating: only low FODMAP superior (RR 0.55, 0.37-0.80). Bowel habit: no diet superior to control. Most comparisons low or very low confidence; direct low-FODMAP and starch/sucrose-reduced vs habitual diet moderate confidence.
- Absolute risks
Not reported in abstract
- Authors' conclusion
Most evidence exists for a low FODMAP diet; other promising diets (e.g., starch- and sucrose-reduced) need more study.
6. Strengths
- Comprehensive, recent
- Network design allows indirect comparisons
- Confidence ratings provided
7. Weaknesses
- Diet trials cannot be blinded well
- Starch/sucrose-reduced diet based on only 2 trials
- Overlaps with earlier NMA by the same group (I-LEG-13)
8. Risk of bias
- Orienting tool
- AMSTAR 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- low
- Rationale
Registered methods typical of this group; main limitation is risk of bias of included diet trials.
9. Assessment of the statistical interpretation
RR is for symptoms NOT improving; RR 0.41 means fewer non-responders, not a cure rate. Overlapping with I-LEG-13; count once.
10. Relevance to the specific claim
Most comprehensive evidence that changing diet (including reducing starch and sugar) improves IBS symptoms for some patients.
11. Independent contrary findings
Many patients do not respond; bowel habit not improved by any diet.
12. Transferability to Germany and Europe
Trials mainly Western; the principle (FODMAP/starch/sugar reduction) applies broadly.
13. Overall methodological judgement
Supports the direction of C-GUT-01 for IBS; contradicts near-universal cure claims.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | high |
| Risk of bias | low |
| Precision of results | moderate |
| Directness | direct |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Long-term effects; trials of bread/wheat removal in Middle-Eastern diets.
15. Linked fact checks
- Reflux (heartburn) and irritable bowel syndrome are largely driven by eating habits; removing white/baladi bread, baked goods and soft drinks can improve symptoms. – Studies supporting the claim
- Stopping bread and baked goods for five days will improve 85% of reflux and IBS symptoms within at most ten days; both diseases can be eliminated completely. – Studies contradicting or limiting the claim