Egg-yolk phosphatidylcholine is converted by gut bacteria into TMAO, and therefore eggs raise the risk of major cardiovascular events (about 2.5-fold).
Original statement
تحدّي صفار البيض الغذائي يرفع مستوى مستقلب TMAO الناتج عن بكتيريا الأمعاء، وارتفاع TMAO في الدم يرتبط بزيادة خطر الحوادث القلبية الوعائية الكبرى بمعدل 2.5 ضعف.
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
Egg-yolk phosphatidylcholine is converted by gut bacteria into TMAO, and therefore eggs raise the risk of major cardiovascular events (about 2.5-fold).
Origin
- Source status
- Archive editors
- Attribution
- Archive editors (not Elawady)
- Origin
- https://eltayebat.com/rule/industrial-eggs/
- Attribution uncertainty
- Narrative and study selection written by the archive operators; the archive states the forbidden section is documented independently of Dr. Diaa's words.
- Claimed mechanism
Gut-microbial metabolism of choline/phosphatidylcholine to trimethylamine and then TMAO, which is proatherogenic.
- Claimed health effect
Major adverse cardiovascular events.
- Population concerned
general population (not specified)
- Geographic restriction by Elawady
none found
Scientific assessment
Mostly false – Essential parts of the statement are not supported by the evidence or are strongly exaggerated.
Certainty of evidence: moderate – Further research may still affect the assessment.
1. What was claimed?
Egg yolk is turned into TMAO by gut bacteria, and high TMAO is linked to a 2.5-fold risk of heart attack, stroke or death.
2. What is demonstrably correct?
Tang et al. (NEJM 2013) showed in a challenge study (40 people; antibiotic sub-study 6 people) that after two hard-boiled eggs plus labelled phosphatidylcholine, TMAO rose and that this depended on gut bacteria. A dose-response feeding study (6 volunteers) found that 2 or more egg yolks acutely raised plasma and urine TMAO, without changes in inflammation or LDL oxidation (I-EGG-134). In 4,007 cardiology patients, the highest vs lowest quartile of plasma TMAO had an unadjusted HR of 2.54 (1.96-3.28); after adjustment the HR was 1.43 (1.05-1.94). A meta-analysis confirms that high TMAO is associated with major cardiovascular events (HR 1.67, I-EGG-114).
3. What is wrong or exaggerated?
The archive's '2.5-fold' figure is the unadjusted hazard ratio, and it refers to blood TMAO levels in patients undergoing coronary angiography, not to eating eggs; egg intake was not measured in the outcome cohort (A-EGG-13). Randomized trials show that eating eggs does not raise fasting TMAO: 4 eggs daily for 4 weeks had no significant effect (I-EGG-10), and a meta-analysis of RCTs found no change (WMD -0.08 umol/L, -0.47 to 0.32; I-EGG-113). Genetic (Mendelian randomization) evidence suggests TMAO may be a marker rather than a cause of heart disease (I-EGG-115). Cohort data on egg intake and CVD do not show the risk implied (C-EGG-04).
4. What remains unclear?
Whether TMAO is a cause or a marker of cardiovascular risk (e.g., of kidney function) is still debated.
5. Which studies support it?
A-EGG-13 (mechanism and TMAO-outcome association); I-EGG-114 (TMAO-MACCE association, HR 1.67); I-EGG-134 (acute post-meal TMAO rise after >=2 egg yolks).
6. Which studies contradict it?
I-EGG-113 (meta-analysis of RCTs: eggs do not change circulating TMAO); I-EGG-10 (eggs did not raise fasting TMAO); I-EGG-115 (Mendelian randomization: TMAO not causal for CVD); I-EGG-01, I-EGG-02 (no association of egg intake with CVD).
7. What applies to Germany and Europe?
Not region-specific.
8. What is known about Egypt?
Not region-specific.
9. What practical conclusion is appropriate?
The TMAO pathway does not provide evidence that eggs in usual amounts increase cardiovascular events; trials show eggs do not raise fasting TMAO.
Assessment details
- Rationale for certainty of evidence
A 2025 meta-analysis of randomized trials (NutriGRADE moderate, I2 23%) found that egg consumption does not change circulating TMAO (I-EGG-113), consistent with a 4-week RCT (I-EGG-10). Mendelian randomization suggests that TMAO is not causal for CAD, MI or stroke and that diabetes and kidney disease raise TMAO (I-EGG-115). The archive's 2.5-fold figure is the unadjusted hazard ratio for TMAO quartiles in cardiology patients, not an effect of eating eggs. Not “False” because eggs can acutely raise post-meal TMAO (I-EGG-134) and high TMAO is a genuine risk marker (I-EGG-114).
- Source quality
Archive featured card; the cited NEJM study is real and correctly quoted, but the archive's derivation (eggs -> 2.5-fold risk) merges two separate parts of the study.
- Regional transferability
Biological mechanism; not region-dependent.
- Individual exceptions
People with impaired kidney function have higher TMAO levels; relevance of dietary choline sources in them is less clear.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 26 October 2026 provisional
Scientific evidence in detail
Overinterpreted – A real finding exists, but the claim draws more from it than the data allow (e.g. association taken as cause, animal data applied to humans, small effect presented as large).
Research question: Does egg-yolk phosphatidylcholine, via gut-microbial TMAO, raise the risk of major cardiovascular events (about 2.5-fold) in people who eat eggs?
Research question in detail (PICO)
- Population
- Adults
- Intervention or exposure
- Egg consumption (and resulting TMAO)
- Comparison
- No/low egg consumption
- Geographic scope
- universal biology
- Outcomes
- plasma TMAO
- major adverse cardiovascular events
- causal role of TMAO
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
Gut bacteria, TMAO and heart risk
Tang WH et al.. N Engl J Med 2013 · PMID 23614584 · DOI 10.1056/NEJMoa1109400 Cohort studyfull text, structured risk-of-bias assessmentTang 2013: eggs plus labelled phosphatidylcholine raised TMAO in a gut-flora-dependent way; high TMAO predicted events in cardiology patients.
- Actual result
- Highest vs lowest TMAO quartile: unadjusted HR 2.54 (1.96-3.28); adjusted HR 1.43 (1.05-1.94).
- Methodological quality
- moderate (mechanistic challenge + cohort of cardiology patients)
- Relevance
- indirect: egg intake not measured in the outcome cohort
- Limitations
- The 2.5-fold figure is unadjusted.
High TMAO in blood is linked to heart events
Schiattarella GG et al.. Eur Heart J 2017 · PMID 29020409 · DOI 10.1093/eurheartj/ehx342 Meta-analysisabstract checkednewly addedMeta-analysis: high plasma TMAO is associated with MACCE and mortality.
- Actual result
- MACCE HR 1.67 (1.33-2.11); mortality HR 1.91 (1.40-2.61); +7% mortality per 10 umol/L.
- Methodological quality
- moderate
- Relevance
- indirect (biomarker, not eggs)
- Limitations
- I2 94% for mortality; confounding by kidney function.
Eggs briefly raise TMAO after a meal
Miller CA et al.. Am J Clin Nutr 2014 · PMID 24944063 · DOI 10.3945/ajcn.114.087692 Randomised controlled trialabstract checkednewly addedDose-response feeding study: >=2 egg yolks acutely raised plasma and urine TMAO.
- Actual result
- About 14% of egg choline converted to TMAO; no change in hsCRP or oxidised LDL.
- Methodological quality
- low (n = 6)
- Relevance
- direct for the mechanistic step
- Limitations
- Acute; tiny sample; industry co-funding.
What speaks against the claim?
Eating eggs does not raise TMAO in blood tests
Aryaeian N et al.. Nutr J 2025 · PMID 41146117 · DOI 10.1186/s12937-025-01227-0 Meta-analysisabstract checkednewly addedMeta-analysis of RCTs: egg consumption did not change circulating TMAO.
- Actual result
- TMAO WMD -0.08 umol/L (-0.47 to 0.32), I2 23%; NutriGRADE moderate.
- Methodological quality
- moderate (RCT meta-analysis)
- Relevance
- direct for the egg -> TMAO step
- Limitations
- Few small trials.
Do eggs raise TMAO? A trial
Wilcox J et al.. Am J Med 2021 · PMID 33872583 · DOI 10.1016/j.amjmed.2021.03.016 Randomised controlled trialfull text, structured risk-of-bias assessmentRCT: 4 eggs/day for 4 weeks did not raise fasting TMAO; choline tablets did.
- Actual result
- Eggs 2.0 -> 2.3 umol/L (P = 0.20); choline 1.9 -> 11.1 umol/L.
- Methodological quality
- moderate (small RCT)
- Relevance
- direct
- Limitations
- 4 weeks; healthy volunteers.
Genetic study: TMAO may be a marker, not a cause, of heart disease
Jia J et al.. Diabetes 2019 · PMID 31167879 · DOI 10.2337/db19-0153 Otherabstract checkednewly addedMendelian randomization: genetically higher TMAO not associated with CAD, MI or stroke; diabetes and kidney disease raise TMAO.
- Actual result
- Null MR for CVD outcomes after Bonferroni correction.
- Methodological quality
- moderate
- Relevance
- indirect: questions TMAO causality
- Limitations
- MR assumptions.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
Eggs may briefly raise TMAO after a meal, but they do not raise fasting TMAO over weeks; TMAO is associated with cardiovascular events but may be a marker of kidney/metabolic disease rather than a cause. The '2.5-fold' figure refers to unadjusted TMAO quartiles in cardiology patients, not to eating eggs.
Why some studies weigh more
RCTs and an RCT meta-analysis directly test the egg -> TMAO step and outweigh the acute 6-person study. MR evidence addresses causality better than observational biomarker studies.
Is a causal relationship established? Not established Neither the egg -> sustained TMAO step nor the TMAO -> CVD causal step is established.
Remaining uncertainty
Clinical relevance of post-meal TMAO peaks; people with kidney disease.
Justified conclusion
The TMAO argument does not show that eggs raise cardiovascular events, and certainly not 2.5-fold.
Why do studies seem to disagree?
Miller 2014 (acute rise) vs Wilcox 2021 and Aryaeian 2025 (no fasting change): different endpoints (post-meal vs fasting) and durations; they are compatible. Recalculation: even at the upper CI of the RCT meta-analysis (+0.32 umol/L), the TMAO-mortality dose-response implies a relative change of about 0.2%.
Does this depend on the country?
- General biological effects
- Universal; gut microbiota composition varies between people.
- Eating habits
- Not region-specific.
- Origin of the food
- Not relevant.
- Contaminants
- Not relevant.
- National production conditions
- Not relevant.
- Legal rules
- Not relevant.
- Actual monitoring data
- Not relevant.
A regional difference that changes the conclusion is not supported by robust data.
Statistical re-check
- Unadjusted vs adjusted HR – Log-HR falls from 0.93 to 0.36 after adjustment (62% attenuation); the archive's 2.5-fold uses the unadjusted value. recalculated
- Implied risk from measured TMAO change – Using 1.07 per 10 umol/L (I-EGG-114), +0.3 umol/L (Wilcox egg arm) implies RR 1.002; choline tablets (+9.2) imply RR 1.064. recalculated
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- Change in fasting TMAO with egg consumption
- Starting level
- high (randomised trials)
- Reasons for downgrading
- imprecision (few small trials)
- Result
- moderate
Simplified assessment by a single reviewer, following the GRADE approach; not a formal GRADE panel. GRADE rates the body of evidence for one outcome, not individual studies.
Search strategy
Documented literature searches for this review (search strings in the original database syntax).
| Database | Date | Search | Looking for | Hits | Included |
|---|---|---|---|---|---|
| Europe PMC | 26 October 2026 | TITLE:(egg*) AND (Egypt* OR Iran* OR Arab* OR "Middle East" OR Tehran OR Saudi) AND (cardiovascular OR "coronary" OR "metabolic syndrome" OR diabetes OR mortality) AND (cohort OR prospective) | both directions | 77 | |
| PubMed | 26 October 2026 | (trimethylamine N-oxide[ti] OR TMAO[ti]) AND (cardiovascular[ti] OR mortality[ti]) AND (meta-analysis[pt]) | supporting evidence | 9 | |
| PubMed | 26 October 2026 | (trimethylamine N-oxide[tiab] OR TMAO[tiab]) AND mendelian randomization[ti] | contradicting evidence | 19 | |
| Europe PMC | 26 October 2026 | TITLE:(egg*) AND (TITLE:TMAO OR TITLE:"trimethylamine") AND (TITLE:trial OR TITLE:randomized OR TITLE:randomised OR TITLE:crossover) | both directions | 3 |
Open questions
Long-term trials of eggs and TMAO in people with chronic kidney disease.
How deeply was this checked?
8 linked studies: 3 checked in full text (3 of them with a structured risk-of-bias assessment), 5 on the basis of the abstract, 0 bibliographically only. No formal assessment with two independent reviewers and no independent human expert review has taken place yet.
Last scientific review: 26 October 2026
History of the verdict
- 25 October 2026 · Phase 1 · Initial assessment: Potentially false (low)
- 26 October 2026 · Phase 4 (systematic evidence review) · Verdict changed: Potentially false (low) → Mostly false (moderate)
The evidence base changed: a 2025 meta-analysis of RCTs (moderate certainty, low heterogeneity) found no effect of eggs on circulating TMAO, and Mendelian randomization suggests TMAO is not causal for CVD. Together with the factual misattribution of the 2.5-fold figure, this supports “Mostly false” with moderate certainty. Not “False” because eggs can acutely raise TMAO and TMAO is a real risk marker.
New sources: I-EGG-113 I-EGG-114 I-EGG-115 I-EGG-134
In plain language
The archive says egg yolk is turned into a substance called TMAO by gut bacteria and that this makes heart attacks 2.5 times more likely. The 2.5-fold number comes from comparing heart patients with high and low TMAO blood levels before taking other risk factors into account; after adjustment the difference was about 1.4-fold, and the study did not measure how many eggs these patients ate. Eggs can raise TMAO briefly after a meal, but trials in which people ate eggs for weeks found no rise in their usual TMAO levels. Genetic studies also suggest that TMAO may be a sign of kidney or metabolic disease rather than a cause of heart attacks.
Studies on this claim
Studies supporting the claim (3)
-
Gut bacteria, TMAO and heart risk
Tang WH et al.. N Engl J Med 2013 · PMID 23614584 · DOI 10.1056/NEJMoa1109400Cohort studycited by the Tayebat archivefull text, structured risk-of-bias assessment★ key studyGut bacteria make TMAO from egg-yolk components; heart patients with the highest TMAO had more events (about 1.4-fold after adjustment, 2.5-fold unadjusted); egg eating itself was not studied against outcomes.
Egg-yolk phosphatidylcholine is converted by gut bacteria into TMAO, and therefore eggs raise the risk of major cardiovascular events (about 2.5-fold).
Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Is gut-microbial metabolism of dietary phosphatidylcholine to TMAO linked to adverse cardiovascular events?
- How was the study done?
Human feeding challenge with antibiotic suppression plus prospective cohort of cardiology patients
- How many people, animals or samples were studied?
40 healthy adults (6 given antibiotics) for the egg challenge; 4,007 heart-catheterisation patients for outcomes
- What was actually found?
TMAO rose after eating eggs and was blocked by antibiotics. Highest vs lowest TMAO quartile: HR 2.54 unadjusted, 1.43 (1.05-1.94) after full adjustment, for death, heart attack or stroke within 3 years.
- How large was the observed effect?
Cox regression; HR
- What do the results mean in everyday life?
Shows a mechanism, not the effect of eating eggs.
- What are the study's limitations?
Egg intake not measured in the outcome cohort; effect shrinks markedly after adjustment (incl. kidney function); high-risk population; antibiotic test in only 6 people.
- What does it say about Elawady's specific claim?
Partly supports; does not show eggs cause events.
- Do the results apply to Germany and Europe?
Not region-specific.
- What can explicitly not be concluded from this study?
Cannot show that eating eggs increases cardiovascular events, nor a 2.5-fold risk from eggs.
-
High TMAO in blood is linked to heart events
Schiattarella GG et al.. Eur Heart J 2017 · PMID 29020409 · DOI 10.1093/eurheartj/ehx342Meta-analysisindependent cross-checkabstract checkedPeople with high TMAO had more cardiovascular events (HR 1.67) and deaths (HR 1.91).
High TMAO associated with MACCE (HR 1.67) and mortality; association, not egg-specific.
Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Pool studies of TMAO and outcomes.
- How was the study done?
Meta-analysis.
- How many people, animals or samples were studied?
26,167.
- What was actually found?
Positive association.
- How large was the observed effect?
MACCE HR 1.67 (1.33-2.11).
- What do the results mean in everyday life?
TMAO is a risk marker, but this does not show eggs raise it.
- What are the study's limitations?
Heterogeneous; confounding by kidney disease.
- What does it say about Elawady's specific claim?
Supports the biomarker link only.
- Do the results apply to Germany and Europe?
Universal.
- What can explicitly not be concluded from this study?
It cannot show TMAO causes disease or that eggs matter.
-
Eggs briefly raise TMAO after a meal
Miller CA et al.. Am J Clin Nutr 2014 · PMID 24944063 · DOI 10.3945/ajcn.114.087692Randomised controlled trialindependent cross-checkabstract checkedEating 2 or more egg yolks raised TMAO in blood and urine over the next day, without changes in inflammation markers.
>=2 egg yolks acutely raised plasma/urine TMAO; no change in hsCRP or oxidised LDL.
Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Test whether eggs raise TMAO.
- How was the study done?
Randomized dose-response feeding study.
- How many people, animals or samples were studied?
6 volunteers.
- What was actually found?
Acute TMAO rise; no inflammation change.
- How large was the observed effect?
About 14% of egg choline converted to TMAO.
- What do the results mean in everyday life?
Eggs can briefly raise TMAO, but this has not been shown to harm the heart.
- What are the study's limitations?
Tiny, short study.
- What does it say about Elawady's specific claim?
Supports the mechanism step only.
- Do the results apply to Germany and Europe?
Universal.
- What can explicitly not be concluded from this study?
It cannot show any effect on heart events.
No study in this group is marked as key.
Studies contradicting or limiting the claim (5)
-
Do eggs raise TMAO? A trial
Wilcox J et al.. Am J Med 2021 · PMID 33872583 · DOI 10.1016/j.amjmed.2021.03.016Randomised controlled trialindependent cross-checkfull text, structured risk-of-bias assessment★ key studyEating four eggs a day for four weeks did not raise fasting TMAO; choline pills did.
Egg-yolk phosphatidylcholine is converted by gut bacteria into TMAO, and therefore eggs raise the risk of major cardiovascular events (about 2.5-fold).
Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Do eggs raise TMAO and platelet reactivity?
- How was the study done?
Randomised intervention study with 5 arms, 4 weeks
- How many people, animals or samples were studied?
82 (18+20+16+18+10); Healthy volunteers with normal renal function (median age 28; 41% male; 81% Caucasian)
- What was actually found?
Fasting plasma TMAO did not rise significantly with 4 eggs/day (median 2.0 to 2.3 uM; P=0.20) or with phosphatidylcholine capsules (P=0.27), but rose strongly in all three arms with choline bitartrate tablets (e.g. 1.9 to 11.1 uM; P<0.0001). Platelet reactivity rose only in the choline-tablet arms; eggs P=0.10.
- How large was the observed effect?
Within-arm comparisons
- What do the results mean in everyday life?
Eggs do not appear to raise this heart-risk marker in healthy people.
- What are the study's limitations?
Small arms (10-20); fifth arm added later (not randomised concurrently); no placebo arm; diet not controlled; only fasting samples; 4 weeks; healthy young adults with normal kidneys
- What does it say about Elawady's specific claim?
Contradicts.
- Do the results apply to Germany and Europe?
Not region-specific.
- What can explicitly not be concluded from this study?
Cannot exclude a small or postprandial TMAO rise, nor effects in people with kidney disease, and says nothing about heart attacks or strokes.
-
Eggs and heart disease: 1.7 million people
Drouin-Chartier JP et al.. BMJ 2020 · PMID 32132002 · DOI 10.1136/bmj.m513Meta-analysisindependent cross-checkfull text, structured risk-of-bias assessment★ key studyEating up to one egg a day was not linked to heart disease or stroke.
Egg-yolk phosphatidylcholine is converted by gut bacteria into TMAO, and therefore eggs raise the risk of major cardiovascular events (about 2.5-fold).
Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Is egg intake associated with cardiovascular disease risk?
- How was the study done?
Three prospective US cohorts (NHS, NHS II, HPFS) plus systematic review and dose-response meta-analysis of prospective cohorts (PROSPERO CRD42019129650)
- How many people, animals or samples were studied?
215,618 cohort participants (14,806 CVD events); meta-analysis 33 estimates, 1,720,108 participants, 139,195 CVD events; US women and men free of CVD, diabetes and cancer; meta-analysis of global cohorts
- What was actually found?
Cohorts: an egg a day or more vs <1 per month HR 0.93 (0.82-1.05). Meta-analysis per egg/day: CVD 0.98 (0.93-1.03); Asia 0.92; in people with type 2 diabetes possibly higher risk (1.25, 0.99-1.59).
- How large was the observed effect?
Pooled Cox models; random-effects meta-analysis
- What do the results mean in everyday life?
For most people, an egg a day is not linked to heart risk.
- What are the study's limitations?
Observational; egg eaters had less healthy profiles (residual confounding possible); heterogeneity; few people above one egg a day; possible higher risk in type 2 diabetes is uncertain.
- What does it say about Elawady's specific claim?
Contradicts the archive claim.
- Do the results apply to Germany and Europe?
European cohorts: no association.
- What can explicitly not be concluded from this study?
Cannot prove absence of any effect at high intakes or in people with type 2 diabetes.
-
Eggs, cholesterol and heart disease in 50 countries
Dehghan M et al.. Am J Clin Nutr 2020 · PMID 31965140 · DOI 10.1093/ajcn/nqz348Cohort studyindependent cross-checkabstract checked★ key studyEating an egg a day was not linked to cholesterol levels, heart disease or death.
Egg-yolk phosphatidylcholine is converted by gut bacteria into TMAO, and therefore eggs raise the risk of major cardiovascular events (about 2.5-fold).
Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Is egg intake associated with blood lipids, CVD and mortality across income levels?
- How was the study done?
Prospective cohort analyses of PURE and of patients in ONTARGET/TRANSCEND trials
- How many people, animals or samples were studied?
146,011 (PURE) + 31,544 (trials); PURE general population (21 countries) and patients with vascular disease (ONTARGET/TRANSCEND)
- What was actually found?
PURE >=7 vs <1 egg/week: composite HR 0.96 (0.89-1.04); mortality 1.04 (0.94-1.15); major CVD 0.92 (0.83-1.01); no association with lipids. ONTARGET/TRANSCEND similar (composite 0.97, 0.76-1.25).
- How large was the observed effect?
Cox frailty models
- What do the results mean in everyday life?
Moderate egg intake appears neutral worldwide.
- What are the study's limitations?
Single FFQ; Few very high consumers
- What does it say about Elawady's specific claim?
Contradicts.
- Do the results apply to Germany and Europe?
Includes European countries.
- What can explicitly not be concluded from this study?
Cannot exclude small effects.
-
Eating eggs does not raise TMAO in blood tests
Aryaeian N et al.. Nutr J 2025 · PMID 41146117 · DOI 10.1186/s12937-025-01227-0Meta-analysisindependent cross-checkabstract checked★ key studyPooled trials found no change in TMAO after egg consumption (WMD -0.08 umol/L).
Eggs did not change circulating TMAO in pooled RCTs (WMD -0.08 umol/L).
Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Test whether eggs raise TMAO.
- How was the study done?
Meta-analysis of randomized trials.
- How many people, animals or samples were studied?
5-6 RCTs.
- What was actually found?
No effect on TMAO, choline or betaine.
- How large was the observed effect?
TMAO WMD -0.08 (-0.47 to 0.32) umol/L.
- What do the results mean in everyday life?
The 'eggs -> TMAO -> heart attack' chain breaks at its first step.
- What are the study's limitations?
Few small trials.
- What does it say about Elawady's specific claim?
Contradicts it.
- Do the results apply to Germany and Europe?
Universal.
- What can explicitly not be concluded from this study?
It cannot settle whether TMAO itself harms the heart.
-
Genetic study: TMAO may be a marker, not a cause, of heart disease
Jia J et al.. Diabetes 2019 · PMID 31167879 · DOI 10.2337/db19-0153Otherindependent cross-checkabstract checkedGenetically higher TMAO was not linked to heart attack or stroke; kidney disease raised TMAO.
Genetically higher TMAO not associated with CAD, MI or stroke; kidney disease and diabetes raise TMAO.
Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Test the causal direction between TMAO and disease.
- How was the study done?
Mendelian randomization.
- How many people, animals or samples were studied?
GWAS consortia.
- What was actually found?
No causal effect of TMAO on CVD; diseases raise TMAO.
- How large was the observed effect?
Not significant for CVD outcomes.
- What do the results mean in everyday life?
High TMAO may reflect kidney or metabolic disease rather than cause heart attacks.
- What are the study's limitations?
MR assumptions.
- What does it say about Elawady's specific claim?
Undermines the causal chain.
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
It cannot fully exclude a small causal effect.
No study in this group is marked as key.
Studies with mixed or unclear results (0)
No studies in this group.
Regional context
Germany / EU
Not region-specific.
Egypt
Not region-specific.
- Antibiotic (veterinary drug) residues in poultry meat and eggs
- Antimicrobial use in food animals and antibiotic growth promoters
- Salmonella in laying hens, eggs and broiler chicken
- Dioxins, PCBs and PFAS in eggs and other animal foods
- Import controls and the meaning of RASFF notifications for Egyptian products
What applies in my country?
General scientific assessment
Mostly false The TMAO argument does not hold: trials show eggs do not raise fasting TMAO, and the 2.5-fold figure refers to unadjusted blood levels in heart patients, not to eating eggs.
The following areas of food safety are relevant to this statement:
- Veterinary medicines and antibiotics
- Contaminants (heavy metals, PFAS, PCBs, dioxins, nitrate)
- Pathogens (Salmonella, Campylobacter, etc.)
- Animal husbandry and feed
- Controls, imports, recalls, labelling
Eggs
Choose a country to see the checked information for it.
Limits: legal rules describe what is allowed, not what every single food contains. Measurement data come from samples and are meaningful only together with their method details.
Country of residence or purchase Compare with another country
References
- Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk.. Tang WH et al.. N Engl J Med 2013 · PMID 23614584 · DOI 10.1056/NEJMoa1109400
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