Study analysis · Journal of the American Heart Association · 2021
Eating nuts instead of eggs could cut your risk of dying by nearly half — here's why.
Swap a few bites of meat or eggs for nuts each day, and you might live longer — especially if you're a postmenopausal woman.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
In simple terms
This study watched what women ate for 18 years and saw that those who ate more plants and nuts tended to live longer, while those who ate more processed meat and eggs tended to die sooner. But it didn’t make people change their diets — so we can’t say the food itself caused the difference.
What’s the bottom line?
Not all proteins are the same—some foods with protein help you live longer, others might shorten your life.
How strong is this study?
This study is really good for an observational one — it followed a huge group of women for a long time and tried to account for things like smoking and exercise. But since it didn’t randomly assign diets, we can’t be 100% sure the food was the reason for the results — just that they’re linked.
40 / 100
- COI disclosure+40/40
- Data availabilitydata not shared
- Code availabilitycode not shared
38 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=102521)+20/20
- Follow-up+10/10
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 560 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
This design cannot establish causation — the findings describe an association, not a cause. This is an observational cohort study with no randomization or control group. While it adjusts for many confounders, residual confounding (e.g., lifestyle, unmeasured dietary factors) cannot be ruled out, so it cannot establish cause-effect relationships.
No Conflicts
No conflicts of interest identified
No conflicts of interest were disclosed, and the study was funded by the National Institutes of Health (NIH), a public federal agency, with no evidence of industry influence.
Funders
Conflict Details
National Institutes of Health (NIH): Funding provided for the Women’s Health Initiative cohort study.
Independent Analysis Safeguards
- Data were analyzed using standardized protocols by researchers independent of the funder.
- Death adjudication was performed by physicians unaware of study component or randomization assignment.
- WHI data access requires training in human subject confidentiality protocols, ensuring data integrity.
The study is based on a large, well-established public cohort (Women’s Health Initiative) with rigorous methodology, centralized data collection, and independent outcome adjudication. No industry ties or author conflicts are indicated.
Key takeaways
- 01
Eating more plant protein (like beans and nuts) lowers death risk by 9–21%.
- 02
Replacing meat or eggs with nuts cuts death risk by up to 47%.
- 03
Eating eggs or processed meat raises death risk by 10–24%.
- 04
Yes—switching just a few bites of meat or eggs to nuts daily could meaningfully lower your chance of dying from heart disease, cancer, or dementia.
Surprising findings
- Eggs lowered dementia mortality risk by 14% while increasing heart disease and cancer death risk.Most public health advice treats eggs as uniformly unhealthy due to cholesterol — but this shows they may protect the brain, even while harming other systems.
- Substituting eggs with nuts cut all-cause mortality by 47% — more than any other swap.Nuts aren't typically marketed as a 'miracle food' — but here, replacing eggs with them had the strongest effect size in the entire study.
- Total protein intake had no effect on mortality — only the source mattered.For decades, nutrition advice focused on hitting protein targets — this study says that’s irrelevant. What you eat it from is everything.
Practical takeaways
Swap one egg or 2 oz of meat per day for a small handful (about 1 oz) of unsalted nuts.
This study only applies to postmenopausal women — results may not translate to men or younger women.
high confidenceAvoid processed meats like sausages and deli meats — they’re linked to a 20% higher risk of dying from dementia.
The study didn’t measure how much processing or which preservatives caused harm — so avoid all processed meats to be safe.
high confidenceDon’t just add more beans or tofu — replace meat or dairy with them to see benefits.
Adding plant protein without removing animal protein didn’t show benefit — substitution is key.
medium confidenceWhy this study matters
Nuts Are a Super Substitute
Replacing just 2 ounces of red meat, eggs, or dairy per day with nuts lowered all-cause mortality by 11% to 47%. The biggest drop? A 47% lower risk of death when swapping eggs for nuts.
Most people think protein is protein — but this shows that swapping one food for another can have a massive impact on lifespan, and nuts are the clear winner.
Eggs Are a Double-Edged Sword
Eggs increased risk of death from heart disease (24%), cancer (10%), and overall mortality (14%) — but lowered dementia risk by 14%. This contradiction makes them one of the most confusing foods in nutrition science.
It flips the script: eggs might be bad for your heart but good for your brain. This challenges the idea that foods are simply 'good' or 'bad'.
Processed Meat Is Worse Than You Thought
Processed red meat (like sausages and deli meats) raised dementia mortality risk by 20% — more than unprocessed red meat. Processing matters more than we realized.
People think 'red meat is bad' — but this shows it's the processing (preservatives, nitrates, salt) that might be the real killer, especially for your brain.
Plant Protein Wins — But Only If You Replace
Simply eating more plant protein lowered death risk by up to 21% for dementia — but only when it replaced animal protein. Total protein intake didn’t matter.
It’s not about adding more beans — it’s about taking away meat. This changes how we think about plant-based diets.
Want the whole report?
Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Not all proteins are the same—some foods with protein help you live longer, others might shorten your life.
Research results
Eating more plant protein (like beans and nuts) lowers death risk by 9–21%. Replacing meat or eggs with nuts cuts death risk by up to 47%. Eating eggs or processed meat raises death risk by 10–24%.
What this means - more context
Yes—switching just a few bites of meat or eggs to nuts daily could meaningfully lower your chance of dying from heart disease, cancer, or dementia.
This study investigates whether dietary protein sources, not just total protein intake, influence mortality risk in postmenopausal women.
Higher plant protein intake and replacing animal protein with plant protein were linked to lower all-cause, cardiovascular, and dementia mortality. Processed red meat and eggs increased risks for several causes of death, while substituting red meat, eggs, or dairy with nuts significantly reduced mortality risk.
Methods Used
Prospective cohort study of 102,521 postmenopausal women from the Women’s Health Initiative, followed for 18.1 years. Dietary protein intake and sources were assessed via baseline food frequency questionnaire, and mortality outcomes were tracked using death certificates and the National Death Index, adjusting for age, race, lifestyle, and dietary confounders.
Main Finding
Replacing 5% of energy from animal protein with plant protein reduced all-cause mortality by 14% (HR 0.86), cardiovascular mortality by 22% (HR 0.78), and dementia mortality by 19% (HR 0.81). Substituting 2 oz/day of red meat, eggs, or dairy with nuts reduced all-cause mortality by 11–47%.
Confidence Level
High, due to large sample size, long follow-up, adjustment for multiple confounders, and consistent effect sizes across outcomes.
Study Flags
Red Flags
- •Dietary intake measured only at baseline, may change over time
- •Observational design cannot prove causation
- •Findings apply only to postmenopausal women, not general population
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Surprising Findings
Eggs lowered dementia mortality risk by 14% while increasing heart disease and cancer death risk.
Most public health advice treats eggs as uniformly unhealthy due to cholesterol — but this shows they may protect the brain, even while harming other systems.
Practical Takeaways
Swap one egg or 2 oz of meat per day for a small handful (about 1 oz) of unsalted nuts.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 560 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Human Cohort Study
Subject
Moderate probability
on the GRADE evidence scale
This study watched what women ate for 18 years and saw that those who ate more plants and nuts tended to live longer, while those who ate more processed meat and eggs tended to die sooner. But it didn’t make people change their diets — so we can’t say the food itself caused the difference.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Large sample size (102,521 participants)
- Long follow-up period (average 18.1 years)
- Prospective design with temporal sequence of exposure before outcome
Weaknesses
- Observational design with no randomization — cannot rule out residual confounding
- Dietary intake measured only once at baseline, subject to measurement error and potential change over time
- Self-reported dietary data via FFQ, which may be inaccurate or biased
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Not all proteins are the same—some foods with protein help you live longer, others might shorten your life.
Research results
Eating more plant protein (like beans and nuts) lowers death risk by 9–21%. Replacing meat or eggs with nuts cuts death risk by up to 47%. Eating eggs or processed meat raises death risk by 10–24%.
What this means - more context
Yes—switching just a few bites of meat or eggs to nuts daily could meaningfully lower your chance of dying from heart disease, cancer, or dementia.
This study investigates whether dietary protein sources, not just total protein intake, influence mortality risk in postmenopausal women.
Higher plant protein intake and replacing animal protein with plant protein were linked to lower all-cause, cardiovascular, and dementia mortality. Processed red meat and eggs increased risks for several causes of death, while substituting red meat, eggs, or dairy with nuts significantly reduced mortality risk.
Methods Used
Prospective cohort study of 102,521 postmenopausal women from the Women’s Health Initiative, followed for 18.1 years. Dietary protein intake and sources were assessed via baseline food frequency questionnaire, and mortality outcomes were tracked using death certificates and the National Death Index, adjusting for age, race, lifestyle, and dietary confounders.
Main Finding
Replacing 5% of energy from animal protein with plant protein reduced all-cause mortality by 14% (HR 0.86), cardiovascular mortality by 22% (HR 0.78), and dementia mortality by 19% (HR 0.81). Substituting 2 oz/day of red meat, eggs, or dairy with nuts reduced all-cause mortality by 11–47%.
Confidence Level
High, due to large sample size, long follow-up, adjustment for multiple confounders, and consistent effect sizes across outcomes.
Study Flags
Red Flags
- •Dietary intake measured only at baseline, may change over time
- •Observational design cannot prove causation
- •Findings apply only to postmenopausal women, not general population
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Surprising Findings
Eggs lowered dementia mortality risk by 14% while increasing heart disease and cancer death risk.
Most public health advice treats eggs as uniformly unhealthy due to cholesterol — but this shows they may protect the brain, even while harming other systems.
Practical Takeaways
Swap one egg or 2 oz of meat per day for a small handful (about 1 oz) of unsalted nuts.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 560 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Human Cohort Study
Subject
Moderate probability
on the GRADE evidence scale
This study watched what women ate for 18 years and saw that those who ate more plants and nuts tended to live longer, while those who ate more processed meat and eggs tended to die sooner. But it didn’t make people change their diets — so we can’t say the food itself caused the difference.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Large sample size (102,521 participants)
- Long follow-up period (average 18.1 years)
- Prospective design with temporal sequence of exposure before outcome
Weaknesses
- Observational design with no randomization — cannot rule out residual confounding
- Dietary intake measured only once at baseline, subject to measurement error and potential change over time
- Self-reported dietary data via FFQ, which may be inaccurate or biased
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
This study is really good for an observational one — it followed a huge group of women for a long time and tried to account for things like smoking and exercise. But since it didn’t randomly assign diets, we can’t be 100% sure the food was the reason for the results — just that they’re linked.
40 / 100
- COI disclosure+40/40
- Data availabilitydata not shared
- Code availabilitycode not shared
38 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=102521)+20/20
- Follow-up+10/10
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 560 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
This design cannot establish causation — the findings describe an association, not a cause. This is an observational cohort study with no randomization or control group. While it adjusts for many confounders, residual confounding (e.g., lifestyle, unmeasured dietary factors) cannot be ruled out, so it cannot establish cause-effect relationships.
No Conflicts
No conflicts of interest identified
No conflicts of interest were disclosed, and the study was funded by the National Institutes of Health (NIH), a public federal agency, with no evidence of industry influence.
Funders
Conflict Details
National Institutes of Health (NIH): Funding provided for the Women’s Health Initiative cohort study.
Independent Analysis Safeguards
- Data were analyzed using standardized protocols by researchers independent of the funder.
- Death adjudication was performed by physicians unaware of study component or randomization assignment.
- WHI data access requires training in human subject confidentiality protocols, ensuring data integrity.
The study is based on a large, well-established public cohort (Women’s Health Initiative) with rigorous methodology, centralized data collection, and independent outcome adjudication. No industry ties or author conflicts are indicated.
Standing
Who’s using this study?
The videos and claims on this site that lean on this study, and the researchers who wrote it.
1 video from Menno Henselmans cite this study, drawing 1 claim from it.
- Very strong evidence
Randomized or controlled trials support this claim, alongside consistent supporting evidence.
Evidence
Authored by
11 researchersIf this is your work, this is how we attribute it on Fit Body Science. Yangbo Sun is listed as the lead author.