Eating half an egg more each day is linked to a small but measurable increase in heart disease risk over decades, but this link disappears when accounting for the cholesterol in eggs—suggesting cholesterol, not eggs themselves, is the main driver of risk.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
A systematic review and meta-analysis of cohort studies that stratify egg intake by dietary cholesterol content would determine whether the association between eggs and CVD is consistent across populations with varying cholesterol intake.
A systematic review and meta-analysis of 15+ prospective cohort studies that report both egg consumption and total dietary cholesterol intake, with stratified analyses of CVD risk by egg intake within low-, medium-, and high-cholesterol diet groups, adjusting for saturated fat and overall diet quality.
A randomized trial comparing egg consumption versus cholesterol-matched non-egg sources would determine whether eggs themselves confer additional risk beyond cholesterol.
A double-blind, randomized trial of 1,000 adults with no CVD, assigned to consume either 1 egg per day (providing ~186 mg cholesterol) or a cholesterol-matched placebo (e.g., 186 mg cholesterol from cholesterol-free supplements + plant sterols) for 12 months, measuring LDL cholesterol, arterial stiffness, and inflammatory markers as primary outcomes.
A prospective cohort study measuring both egg intake and cholesterol intake separately could confirm whether the association between eggs and CVD disappears when cholesterol is accounted for.
A prospective cohort of 8,000 US adults with annual dietary assessments of egg consumption and total dietary cholesterol, followed for 20 years with adjudicated CVD events, adjusting for saturated fat, animal protein, and diet quality scores.
A case-control study could compare egg consumption patterns in individuals with and without CVD, while controlling for total cholesterol intake, to assess whether eggs independently contribute to risk.
A matched case-control study of 1,500 adults with incident CVD and 1,500 without, matched for age, sex, and total dietary cholesterol intake, with detailed dietary recall of egg consumption over the prior 5 years, adjusting for smoking and physical activity.
A cross-sectional study could examine whether higher egg intake correlates with higher LDL cholesterol levels, independent of total dietary cholesterol intake.
A cross-sectional analysis of 3,000 adults measuring egg consumption via food frequency questionnaire and serum LDL cholesterol levels, adjusting for total dietary cholesterol, saturated fat, and BMI.