Meta-analysisindependent cross-checkabstract only checked I-MEAT-09 standard review
Heme iron from meat linked to colon cancer
Heme iron from meat and risk of colorectal cancer: a meta-analysis and a review of the mechanisms involved.
Overview
Bastide NM et al.. Cancer Prev Res (Phila) 2011 · PMID 21209396 · DOI 10.1158/1940-6207.CAPR-10-0113
Highest vs lowest heme intake RR 1.18.
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?
Heme and colon cancer.
- How was the study done?
Meta-analysis + mechanism review.
- How many people, animals or samples were studied?
566,607 people.
- What was actually found?
Modest association.
- How large was the observed effect?
RR 1.18 (1.06-1.32).
- What do the results mean in everyday life?
Plausible reason to limit red meat.
- What are the study's limitations?
Observational.
- What does it say about Elawady's specific claim?
Supports limiting red meat.
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
Risk at low intakes.
Scientific in-depth review
1. Full reference
- Authors
- Bastide NM et al.
- Journal
- Cancer Prev Res (Phila)
- Year
- 2011
- Identifier
- PMID 21209396 DOI 10.1158/1940-6207.CAPR-10-0113
- Verification
- verified – PubMed efetch 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
not stated in abstract
2. Research question
Heme iron intake and colon cancer.
3. Study design and population
- Study design
- Meta-analysis – Meta-analysis of prospective cohorts plus review of mechanisms (incl. rat studies).
- Population
566,607 individuals; 4,734 cases
- Country
Multinational
- Period
Not stated
- Sample size
Prospective cohorts (number not in abstract)
- Inclusion and exclusion criteria
Cohorts reporting heme intake.
4. Methods and endpoints
- Exposure / intervention
Heme iron
- Comparator
Lowest category
- Endpoints
Colon cancer.
- Statistical methods
Meta-analysis.
5. Actual results
- Results
Highest vs lowest heme iron: colon cancer RR 1.18 (1.06-1.32); rat studies: dietary haemoglobin and red meat promote aberrant crypt foci; mechanisms via N-nitroso compounds and lipid peroxidation.
- Absolute risks
not reported
- Authors' conclusion
Suggestive association between dietary heme and colon cancer; both catalytic pathways likely involved.
6. Strengths
- Combines epidemiology and mechanisms
7. Weaknesses
- Observational; heme estimates from FFQ
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
Abstract-level.
9. Assessment of the statistical interpretation
Modest RR.
10. Relevance to the specific claim
Supporting C-MEAT-01 (mechanism); heme iron is also the nutritional benefit of red meat and liver.
11. Independent contrary findings
n/a
12. Transferability to Germany and Europe
Moderate.
13. Overall methodological judgement
Heme iron a plausible mechanism.
| 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 | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Balance with iron deficiency.
15. Linked fact checks
- Red meat should be limited: beef/buffalo at most once a week and lamb twice a week (protein not every day). – Studies supporting the claim