Meta-analysisindependent cross-checkabstract only checked I-LEG-13 standard review
Low-FODMAP diet for IBS
Efficacy of a low FODMAP diet in irritable bowel syndrome: systematic review and network meta-analysis.
Overview
Black CJ et al.. Gut 2022 · PMID 34376515 · DOI 10.1136/gutjnl-2021-325214
Across 13 trials, a low-FODMAP diet was the most effective diet for IBS symptoms.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Compare IBS diets
- How was the study done?
Network meta-analysis
- How many people, animals or samples were studied?
944
- What was actually found?
Low-FODMAP best
- How large was the observed effect?
RR 0.67
- What do the results mean in everyday life?
Helps IBS patients.
- What are the study's limitations?
Unblinded
- What does it say about Elawady's specific claim?
IBS-specific
- Do the results apply to Germany and Europe?
High
- What can explicitly not be concluded from this study?
Cannot support avoidance by healthy people.
Scientific in-depth review
1. Full reference
- Authors
- Black CJ et al.
- Journal
- Gut
- Year
- 2022
- Identifier
- PMID 34376515 DOI 10.1136/gutjnl-2021-325214
- Verification
- verified – PubMed efetch 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
None declared
2. Research question
Efficacy of low-FODMAP vs other diets in IBS.
3. Study design and population
- Study design
- Meta-analysis – Systematic review and network meta-analysis of RCTs
- Population
IBS patients
- Country
Multiple
- Period
Search to April 2021
- Sample size
13 RCTs; 944 patients
- Inclusion and exclusion criteria
RCTs of low-FODMAP diet in IBS
4. Methods and endpoints
- Exposure / intervention
Low-FODMAP diet
- Comparator
Habitual diet, BDA/NICE advice, others
- Endpoints
Global symptoms, pain, bloating, bowel habit
- Statistical methods
Random-effects NMA, P-scores
5. Actual results
- Results
RR of symptoms not improving vs habitual diet 0.67 (95% CI 0.48-0.91); superior to BDA/NICE advice for bloating (RR 0.72; 0.55-0.94).
- Absolute risks
not reported
- Authors' conclusion
Low-FODMAP ranked first for all endpoints; most trials in secondary/tertiary care; reintroduction not studied.
6. Strengths
- Network approach
7. Weaknesses
- Blinding issues
- No reintroduction data
8. Risk of bias
- Orienting tool
- AMSTAR 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Diet trials hard to blind.
9. Assessment of the statistical interpretation
Moderate effect.
10. Relevance to the specific claim
Supports C-LEG-12 for IBS only.
11. Independent contrary findings
None.
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
Supports IBS-specific restriction.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | moderate |
| Directness | indirect |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Long-term effects.