Cohort studycited by the Tayebat archiveabstract only checked★ key study A-EGG-12 in-depth review
Eggs, cholesterol and heart disease in six US cohorts
Associations of Dietary Cholesterol or Egg Consumption With Incident Cardiovascular Disease and Mortality.
Overview
Zhong VW et al.. JAMA 2019 · PMID 30874756 · DOI 10.1001/jama.2019.1572
More eggs or dietary cholesterol were linked to slightly more heart disease and deaths; the egg link disappeared when cholesterol intake was accounted for.
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?
Are dietary cholesterol or egg consumption associated with incident CVD and all-cause mortality?
- How was the study done?
Pooled individual-participant analysis of 6 prospective US cohorts
- How many people, animals or samples were studied?
29,615 participants; 5,400 CVD events; 6,132 deaths; US adults (mean age 51.6; 31.1% black)
- What was actually found?
Per 300 mg cholesterol/day: CVD HR 1.17 (1.09-1.26), ARD 3.24%; mortality HR 1.18 (1.10-1.26), ARD 4.43%. Per half egg/day: CVD HR 1.06 (1.03-1.10), ARD 1.11% (0.32-1.89); mortality HR 1.08 (1.04-1.11), ARD 1.93%. After adjustment for dietary cholesterol, egg associations were no longer significant (CVD HR 0.99, 0.93-1.05; mortality HR 1.03, 0.97-1.09).
- How large was the observed effect?
Cox models; HR and absolute risk difference (ARD)
- What do the results mean in everyday life?
Absolute differences were about 1-2 percentage points over 17 years.
- What are the study's limitations?
Single baseline dietary assessment; Residual confounding; US-only
- What does it say about Elawady's specific claim?
Supports the claim but is contradicted by larger meta-analyses.
- Do the results apply to Germany and Europe?
Moderate; European cohorts show no association (I-EGG-01).
- What can explicitly not be concluded from this study?
Cannot prove causation.
Scientific in-depth review
1. Full reference
- Authors
- Zhong VW, Van Horn L, Cornelis MC, Wilkins JT, Ning H, Carnethon MR, Greenland P, Mentz RJ, Tucker KL, Zhao L, Norwood AF, Lloyd-Jones DM, Allen NB
- Journal
- JAMA
- Year
- 2019
- Identifier
- PMID 30874756 DOI 10.1001/jama.2019.1572 · PMC6439941
- Verification
- verified – PubMed E-utilities efetch, 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
No COI statement in record; NHLBI/NIDDK funding
2. Research question
Are dietary cholesterol or egg consumption associated with incident CVD and all-cause mortality?
3. Study design and population
- Study design
- Cohort study – Pooled individual-participant analysis of 6 prospective US cohorts
- Population
US adults (mean age 51.6; 31.1% black)
- Country
USA
- Period
1985-2016 (median follow-up 17.5 years)
- Sample size
29,615 participants; 5,400 CVD events; 6,132 deaths
- Inclusion and exclusion criteria
Six US cohorts with harmonised diet data
4. Methods and endpoints
- Exposure / intervention
Dietary cholesterol (mg/day); eggs (number/day)
- Comparator
Lower intake (continuous)
- Endpoints
Incident CVD (composite), all-cause mortality
- Statistical methods
Cox models; HR and absolute risk difference (ARD)
5. Actual results
- Results
Per 300 mg cholesterol/day: CVD HR 1.17 (1.09-1.26), ARD 3.24%; mortality HR 1.18 (1.10-1.26), ARD 4.43%. Per half egg/day: CVD HR 1.06 (1.03-1.10), ARD 1.11% (0.32-1.89); mortality HR 1.08 (1.04-1.11), ARD 1.93%. After adjustment for dietary cholesterol, egg associations were no longer significant (CVD HR 0.99, 0.93-1.05; mortality HR 1.03, 0.97-1.09).
- Absolute risks
ARD 1.11% (CVD) and 1.93% (mortality) per half egg/day over follow-up
- Authors' conclusion
Higher dietary cholesterol or egg intake associated with higher CVD and mortality risk in a dose-response manner; should be considered in guidelines.
6. Strengths
- Large pooled IPD
- Long follow-up
- Reports absolute risk
7. Weaknesses
- Single baseline dietary assessment
- Residual confounding
- US-only
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Diet measured once; confounding possible.
9. Assessment of the statistical interpretation
Small relative and absolute differences; association with eggs explained by cholesterol content.
10. Relevance to the specific claim
11. Independent contrary findings
12. Transferability to Germany and Europe
Moderate; European cohorts show no association (I-EGG-01).
13. Overall methodological judgement
High-profile but outlying finding within the total evidence.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | high |
| Directness | direct |
| Reproducibility | not replicated |
| Consistency with the overall evidence | inconsistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | essentially correct but incomplete |
14. Open questions
Why US cohorts differ.
15. Linked fact checks
Use by the Tayebat archive
Note: according to the archive, the studies were compiled by the archive operators. Whether Dr. Elawady himself cited this study is not established.
- What the archive says about the study
Each additional half egg per day was linked to a 6% higher CVD risk and 8% higher all-cause mortality across 29,615 US adults.
- A. What was actually studied?
Egg and cholesterol intake vs CVD and death in US cohorts.
- B. What did the authors find?
Numbers as quoted; egg effect not significant after adjusting for cholesterol.
- C. What conclusions do the authors themselves draw?
Higher cholesterol or egg intake associated with risk.
- D. What does the archive derive from it?
Used as epidemiological evidence that eggs harm the heart.
- E. Is this derivation scientifically justified?
Essentially correct but incomplete: absolute risks and the larger contradicting meta-analytic evidence are omitted.
- Adequacy of the interpretation (by the archive)
- essentially correct but incomplete