Systematic reviewindependent cross-checkabstract only checked★ key study I-FSH-03 in-depth review
Fish: benefits vs contaminant risks (2006)
Fish intake, contaminants, and human health: evaluating the risks and the benefits.
Overview
Mozaffarian D & Rimm EB. JAMA 2006 · PMID 17047219 · DOI 10.1001/jama.296.15.1885
For adults, the benefits of eating fish 1-2 times a week outweigh risks from contaminants.
Does the study support the specific claim? No · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Weigh benefits and risks.
- How was the study done?
Review/meta-analysis.
- How many people, animals or samples were studied?
Many studies.
- What was actually found?
Benefits > risks.
- How large was the observed effect?
Coronary death -36%.
- What do the results mean in everyday life?
Eat fish, vary species.
- What are the study's limitations?
Mostly observational.
- What does it say about Elawady's specific claim?
Contradicts 'avoid farmed salmon'.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Species-specific risks for every fish.
Scientific in-depth review
1. Full reference
- Authors
- Mozaffarian D & Rimm EB
- Journal
- JAMA
- Year
- 2006
- Identifier
- PMID 17047219 DOI 10.1001/jama.296.15.1885
- Verification
- verified – PubMed efetch 2026-10-25
- Retracted
- no
- Corrections
ErratumIn: JAMA. 2007 Feb 14;297(6):590
- Extent checked
- abstract only
- Conflicts of interest and funding
not stated in abstract/record
2. Research question
Do benefits of fish intake outweigh contaminant risks?
3. Study design and population
- Study design
- Systematic review – Review with meta-analyses of fish intake benefits and contaminant risks
- Population
Adults, women of childbearing age
- Country
Global (US-led)
- Period
literature to April 2006
- Sample size
not stated in abstract
- Inclusion and exclusion criteria
RCTs, prospective studies, meta-analyses, government reports
4. Methods and endpoints
- Exposure / intervention
Fish/fish oil intake; MeHg; dioxins/PCBs
- Endpoints
Coronary death, total mortality, neurodevelopment
- Statistical methods
Meta-analysis where possible
5. Actual results
- Results
1-2 servings/week reduce coronary death by 36% (95% CI 20%-50%) and total mortality by 17% (0%-32%); dioxin/PCB levels in fish low and potential effects outweighed by benefits; MeHg may affect early neurodevelopment; women of childbearing age 2 servings/week, limiting selected species.
- Absolute risks
not reported
- Authors' conclusion
'For major health outcomes among adults ... the benefits of fish intake exceed the potential risks.'
6. Strengths
- Comprehensive
- JAMA
7. Weaknesses
- Not fully systematic
- Observational basis for many outcomes
- Erratum (JAMA 2007;297:590)
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
Narrative-systematic hybrid; no formal risk-of-bias appraisal in abstract.
9. Assessment of the statistical interpretation
Relative risk reductions from pooled observational data.
10. Relevance to the specific claim
Contradicts C-FSH-03/05; supports benefit part of C-FSH-14; mixed for C-FSH-02.
11. Independent contrary findings
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
Standard reference for benefit-risk.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | moderate |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Updated estimates.
15. Linked fact checks
- Farmed fish today accumulate PCBs, dioxins and PBDEs at concentrations significantly higher than in their wild counterparts (present-tense generalisation in the archive summary). – Studies with mixed or unclear results
- Farmed Atlantic salmon from northern Europe should be eaten no more than once every five months to stay below an acceptable cancer-risk threshold (and, per the archive's card for Foran 2005, dioxin-contaminated farmed salmon less than once a month). – Studies contradicting or limiting the claim
- Because of the lower omega-3:omega-6 ratio, farmed salmon is converted from an anti-inflammatory into a pro-inflammatory meal, and the expected nutritional benefit disappears. – Studies contradicting or limiting the claim
- Natural wild sea fish is the cleanest food you can get; wild sea fish (including large predators such as grouper/hamour, tuna, and smoked mackerel) is allowed while farmed fish is forbidden. – Studies supporting the claim