Meta-analysisindependent cross-checkabstract only checked I-CHK-14 standard review
Cooking mutagens and colorectal cancer
Dietary Intake of Meat Cooking-Related Mutagens (HCAs) and Risk of Colorectal Adenoma and Cancer: A Systematic Review and Meta-Analysis.
Overview
Chiavarini M et al.. Nutrients 2017 · PMID 28524104 · DOI 10.3390/nu9050514
Higher intake of cooking-related mutagens was linked to more colorectal polyps and cancer.
Does the study support the specific claim? Yes · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
HCA intake and colorectal adenoma/cancer
- How was the study done?
Systematic review and meta-analysis
- How many people, animals or samples were studied?
39 studies; 15,229 CRA cases; 21,344 CRC cases; Observational studies
- What was actually found?
CRA: PhIP OR 1.20 (1.13-1.28), MeIQx 1.14, DiMeIQx 1.13, B(a)P 1.10, MDM 1.17. CRC: MeIQx OR 1.14 (1.04-1.25), DiMeIQx 1.12, MDM 1.12; PhIP not significant for CRC in abstract.
- How large was the observed effect?
Random effects
- What do the results mean in everyday life?
Avoid charring meat.
- What are the study's limitations?
Mutagen intake estimated from questionnaires; Heterogeneity; Case-control designs
- What does it say about Elawady's specific claim?
Supports HCA concern, not chicken-specific.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Cannot isolate chicken.
Scientific in-depth review
1. Full reference
- Authors
- Chiavarini M et al.
- Journal
- Nutrients
- Year
- 2017
- Identifier
- PMID 28524104 DOI 10.3390/nu9050514
- Verification
- verified – PubMed efetch 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
No conflicts
2. Research question
HCA intake and colorectal adenoma/cancer
3. Study design and population
- Study design
- Meta-analysis – Systematic review and meta-analysis
- Population
Observational studies
- Country
Multinational
- Period
Not stated
- Sample size
39 studies; 15,229 CRA cases; 21,344 CRC cases
- Inclusion and exclusion criteria
Studies estimating meat mutagen intake
4. Methods and endpoints
- Exposure / intervention
PhIP, MeIQx, DiMeIQx, B(a)P, MDM
- Comparator
Lowest intake
- Endpoints
Colorectal adenoma, cancer
- Statistical methods
Random effects
5. Actual results
- Results
CRA: PhIP OR 1.20 (1.13-1.28), MeIQx 1.14, DiMeIQx 1.13, B(a)P 1.10, MDM 1.17. CRC: MeIQx OR 1.14 (1.04-1.25), DiMeIQx 1.12, MDM 1.12; PhIP not significant for CRC in abstract.
- Absolute risks
not reported
- Authors' conclusion
Mutagens formed at high temperature may be responsible for meat carcinogenicity.
6. Strengths
- Many studies
7. Weaknesses
- Mutagen intake estimated from questionnaires
- Heterogeneity
- Case-control designs
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
Simplified.
9. Assessment of the statistical interpretation
Modest ORs.
10. Relevance to the specific claim
11. Independent contrary findings
IARC: insufficient data on cooking.
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
Modest supportive evidence for HCA hazard.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | moderate |
| Directness | indirect |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | mixed |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Causality.
15. Linked fact checks
- Grilling or pan-frying chicken breast forms potent carcinogens (PhIP up to 480 ng/g). – Studies supporting the claim