1.7 million people · up to 32 years

Eggs got blamed. Look what was next to them.

People say: “Eggs are bad for your heart” We read the study.

What they did

Meta-analysis of cohort studies. 215,618 people. up to 32 years of follow-up (NHS 1980-2012, NHS II 1991-2013, HPFS 1986-2012), >5.54 million person-years.

Many studies, added up. People were watched, not told what to do. A clue, not proof.

Who: US health professionals: 83,349 women (Nurses' Health Study), 90,214 women (NHS II), 42,055 men (Health Professionals Follow-Up Study), free of cardiovascular disease, type 2 diabetes and cancer at baseline. Meta-analysis: 28 studies, 1,720,108 participants (US, Europe, Asia)

What they found
  • Extra risk: 1 egg a daynone3 US cohorts, adjusted
  • Extra risk: 1.7M peoplenonemeta-analysis
  • Swap egg → processed meat+15%statistical model

Up to 1 egg a day: not linked to heart disease, after adjusting for diet and lifestyle

The catch

Type 2 diabetes: possibly higher risk.

More to know, from our read of the paper:

  • Observational (cohorts + meta-analysis of cohorts): association, not causation. 'Not associated' does not prove eggs are protective or 'healthy'
  • Egg intake self-reported on food frequency questionnaires (whole eggs with yolk; eggs in baked goods, liquid eggs and egg whites excluded from the main exposure)
  • Very few people ate a lot of eggs: in 1998-99 only 1.24% ate at least 1 egg/day and 0.20% at least 2/day; most ate 1 to <5 eggs/week. The authors say this low intake should be taken into account
  • Blood cholesterol was NOT the outcome; the paper measured heart attacks, coronary deaths and strokes, not whether eggs raise LDL
  • Cohorts are US health professionals (mostly white nurses/health workers), possibly not generalisable (stated by the authors)
The verdict

Up to 1 egg a day: no link found.

One thing to try
  1. Up to 1 a day: no linkFew ate more, so higher amounts are less certain.
  2. Watch what's next to themBacon & processed meat: the swap linked to higher risk.
  3. Diabetes? Ask your doctorMore eggs pointed to higher risk; evidence mixed.
In short

3 US cohorts (215,618 health professionals, up to 32 years) + a meta-analysis of 1.7 million people: up to one egg a day was not linked to heart disease after adjusting for diet and lifestyle. Not linked ≠ proven healthy. Possible exception: people with type 2 diabetes. Food was self-reported.

The paper

Drouin-Chartier et al. (2020). Egg consumption and risk of cardiovascular disease: three large prospective US cohort studies, systematic review, and updated meta-analysis. BMJ.

Design: Meta-analysis of cohort studies · three prospective cohort studies + systematic review and meta-analysis of prospective cohort studies (observational: linked, not proven)

DOI: 10.1136/bmj.m513

Goals:

Eat betterHealthy old age
How we checked

We read the abstract and the full text of this paper and checked every number on this page against it (18 facts, checked on 2026-10-01). The study design is named above. Cohort and other observational studies are described as linked, not proven. Found an error? Email theis@onestudyaday.com.

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