What does the research show about eggs?

Eggs

Feeding trials found eggs raise LDL cholesterol by about 8 mg/dL and HDL slightly. Large pooled cohorts mostly found no link between up to one egg a day and heart disease or stroke, though a 2022 analysis found a small rise. Links with type 2 diabetes appeared in US cohorts and not in European or Asian ones.

Add to Bio HackChecked 2026-11-13

Status: A food, not a regulated health product. The Dietary Guidelines for Americans, 2025-2030 list eggs among the animal protein foods to eat as part of a variety of protein foods [1].
Also called: egg, chicken eggs, hen's eggs, egg yolks, whole eggs, egg whites, dietary cholesterol, an egg a day
Studied for: protein, heart health, HDL cholesterol, cholesterol concerns, weight management, blood sugar, nutrition

Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on

Shown to help0

No benefit shown in research yet.

Reported risks5

StrongShown to raise LDL cholesterol by about 8 mg/dL in randomized trials in healthy people, along with total cholesterol and apolipoprotein B.How often is not known
ModerateLinked to 69% more cardiovascular disease at one or more eggs a day than under one a week, in cohorts of people with diabetes.How often is not known
ModerateLinked to 20% higher cancer death at the highest egg intake than the lowest, in pooled cohorts rated low to moderate in certainty.How often is not known
LimitedFDA expected its egg safety rule to prevent about 79,000 illnesses and 30 deaths a year from eggs contaminated with Salmonella Enteritidis.How often is not known
LimitedSelf-reported egg allergy ranged from 0.2% to 7% across studies, in a meta-analysis that found objective tests gave far lower figures than self-report.How often is not known

What it was studied for, and what was found

Mixed results4

Strong

HDL cholesterol and the cholesterol ratio

Shown to raise HDL cholesterol slightly in feeding trials. The ratio of LDL or total cholesterol to HDL rose in two of three pooled analyses.

Compared with diets differing only in dietary cholesterol or number of eggs [2]; control groups eating fewer eggs [3][4]

The numbers and sources

Effect: Each extra 100 mg of dietary cholesterol a day raised HDL by 0.3 mg/dL (95% CI 0.2 to 0.4), total cholesterol by 2.2 mg/dL and the total to HDL cholesterol ratio by 0.020 units (95% CI 0.010 to 0.030) [2]. Across 66 trials, eggs raised HDL and apolipoprotein A1 along with total and LDL cholesterol, with no change in the LDL to HDL ratio [4]. Across 17 trials in healthy people, eating more eggs raised the LDL to HDL ratio by 0.14 (P = 0.001) [3].
Population: 556 participants in 17 controlled feeding studies of at least 14 days [2]. 3,185 participants in 66 randomized trials [4]. Healthy participants in 17 randomized trials [3].
Sources: [2], [4], [3]
Caveats: The pooled analyses disagree on the ratio. Trials ran weeks to months and measured blood lipids, not heart events.

Strong

Heart disease and stroke

Mixed results: most pooled cohorts linked up to one egg a day to no change in heart disease or stroke, while a 2022 analysis found 4% higher risk.

Compared with one fewer egg a day [5][6]; under one egg a week or never [7]; half an egg a day less [8]

The numbers and sources

Effect: Across 33 risk estimates, one more egg a day was not linked to cardiovascular disease (RR 0.98, 95% CI 0.93 to 1.03), coronary heart disease (0.96) or stroke (0.99). It was linked to lower risk in Asian cohorts (0.92, 95% CI 0.85 to 0.99) and not in US or European ones [5]. At 1 or more eggs a day against fewer than 1 a week, cardiovascular disease was not raised (HR 0.96, 95% CI 0.88 to 1.05) [7]. A 2022 update of 49 estimates linked each extra 50 g egg a day to higher risk (RR 1.04, 95% CI 1.00 to 1.08), 1.08 in US cohorts and no link in Asian ones [6]. In 6 pooled US cohorts, each extra half egg a day was linked to higher risk (HR 1.06, 95% CI 1.03 to 1.10), a link that disappeared after adjusting for dietary cholesterol [8].
Population: 1,720,108 participants and 139,195 events [5]. 22 cohorts [7]. 3,601,401 participants and 255,479 events [6]. 29,615 US adults followed a median 17.5 years [8].
Sources: [5], [7], [6], [8]
Caveats: Observational. People eating more eggs in US cohorts had higher BMI, ate more red meat and were less often on statins [5]. Heterogeneity was high in the 2022 update (I² 80.1%) [6]. Results differ by region, which may reflect what eggs are eaten with.

Moderate

Type 2 diabetes

Mixed results: one pooled analysis linked an egg a day to 42% more type 2 diabetes, while a larger update found no overall link, except in US cohorts.

Compared with under one egg a week or never [7]; one fewer egg a day [9]

The numbers and sources

Effect: At 1 or more eggs a day against fewer than 1 a week, type 2 diabetes was higher (HR 1.42, 95% CI 1.09 to 1.86) [7]. Across 16 cohorts, each egg a day was not significantly linked to type 2 diabetes overall (RR 1.07, 95% CI 0.99 to 1.15). It was linked in US studies (RR 1.18, 95% CI 1.10 to 1.27) and not in European (0.99) or Asian (0.82) ones [9].
Population: 22 cohorts [7]. 589,559 participants and 41,248 cases in 16 cohorts [9].
Sources: [7], [9]
Caveats: Observational, with high heterogeneity (I² 69.8%) [9].

Moderate

Death from any cause

Mixed results: the highest egg intake was not linked to death in pooled cohorts, while dose-response models linked each extra egg to slightly higher death.

Compared with the lowest intake [10]; one fewer 50 g egg a day [6]; half an egg a day less [8]

The numbers and sources

Effect: The highest against the lowest intake was not linked to death from any cause (RR 1.02, 95% CI 0.94 to 1.11), heart disease or stroke, while each extra egg a week was linked to 2% higher death [10]. In 27,078 men, each extra 50 g egg a day was linked to higher death (HR 1.06) [6]. In US cohorts, each extra half egg a day was linked to higher death (HR 1.08, 95% CI 1.04 to 1.11), and not after adjusting for dietary cholesterol [8].
Population: 2,216,720 participants and 232,408 deaths in 33 cohorts [10]. 27,078 men in the ATBC study [6]. 29,615 US adults [8].
Sources: [10], [6], [8]
Caveats: Observational. The review rated certainty low to moderate [10].

Amounts studied

Most people in the US cohorts ate 1 to under 5 eggs a week [5]. Cohort reviews compared 1 or more eggs a day with under 1 a week [7], or modeled risk per egg a day [5], per 50 g egg [6] or per half egg [8]. Feeding trials added eggs or dietary cholesterol for at least 14 days [2], and an update reported effects of more than one egg a day over under 12 weeks [4].

Risks

Reported risks5

StrongHow often is not known

Higher LDL cholesterol in feeding trials

Shown to raise LDL cholesterol by about 8 mg/dL in randomized trials in healthy people, along with total cholesterol and apolipoprotein B.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: Against control groups, eating more eggs raised LDL cholesterol (mean difference 8.14 mg/dL, P < 0.0001), with larger effects in trials of over two months [3]. Across 66 trials, eggs raised total cholesterol, LDL and apolipoprotein B100, did not change triglycerides, and LDL rose nonlinearly with dose [4]. Each extra 100 mg of dietary cholesterol a day raised total cholesterol by 2.2 mg/dL (95% CI 1.8 to 2.5) [2].
Population: Healthy participants in 17 randomized trials [3]. 3,185 participants in 66 randomized trials [4]. 556 participants in 17 feeding studies [2].
Sources: [3], [4], [2]
Caveats: Short trials. One review found the rise came with eating more than one egg a day for under 12 weeks [4].

ModerateHow often is not known

Heart disease in people with diabetes

Linked to 69% more cardiovascular disease at one or more eggs a day than under one a week, in cohorts of people with diabetes.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: In studies of people with diabetes, the highest egg intake was linked to overall cardiovascular disease (HR 1.69, 95% CI 1.09 to 2.62) against the lowest [7].
Population: Cohort studies of people with diabetes within a review of 22 cohorts [7].
Sources: [7]
Caveats: Observational, and a subgroup of one review.

ModerateHow often is not known

Cancer death

Linked to 20% higher cancer death at the highest egg intake than the lowest, in pooled cohorts rated low to moderate in certainty.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: The highest against the lowest intake was linked to higher cancer death (RR 1.20, 95% CI 1.04 to 1.39), and each extra egg a week to 4% higher cancer death [10].
Population: 13 cohorts within a review of 2,216,720 participants [10].
Sources: [10]
Caveats: Observational. One review.

LimitedHow often is not known

Salmonella food poisoning

FDA expected its egg safety rule to prevent about 79,000 illnesses and 30 deaths a year from eggs contaminated with Salmonella Enteritidis.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: FDA states that egg-associated Salmonella illness can cause mild to severe gut illness, short-term or chronic arthritis, or death. Its rule requires preventive measures in poultry houses and refrigeration in storage and transport [11].
Population: US population, as estimated by FDA [11].
Sources: [11]
Caveats: A regulator's estimate of illnesses prevented, not a measured rate per egg eaten.

LimitedHow often is not known

Egg allergy

Self-reported egg allergy ranged from 0.2% to 7% across studies, in a meta-analysis that found objective tests gave far lower figures than self-report.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: Self-reported prevalence of egg allergy varied from 0.2% to 7%. Heterogeneity between studies was marked, and self-reported food allergy was very high against objective measures [12].
Population: 51 studies of infants, school children and adults [12].
Sources: [12]
Caveats: The range spans study methods and populations. The authors recommend food challenge testing for prevalence estimates [12].

Claims tested and not found

That eggs raise stroke risk. One more egg a day was not linked to stroke across 22 estimates (RR 0.99, 95% CI 0.91 to 1.07) [5], and the highest intake was not linked to stroke death [10].
That eggs raise triglycerides. Across 66 randomized trials, eggs raised several blood lipids and did not change triglycerides [4].

Sources

US Department of Agriculture and US Department of Health and Human Services. Dietary Guidelines for Americans, 2025-2030. realfood.gov. 2026. https://cdn.realfood.gov/DGA.pdf
Weggemans RM, Zock PL, Katan MB. Dietary cholesterol from eggs increases the ratio of total cholesterol to high-density lipoprotein cholesterol in humans: a meta-analysis. The American Journal of Clinical Nutrition. 2001. https://doi.org/10.1093/ajcn/73.5.885
Li MY, Chen JH, Chen C, Kang YN. Association between Egg Consumption and Cholesterol Concentration: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Nutrients. 2020. https://doi.org/10.3390/nu12071995
Khalighi Sikaroudi M, Soltani S, Kolahdouz-Mohammadi R, et al. The responses of different dosages of egg consumption on blood lipid profile: An updated systematic review and meta-analysis of randomized clinical trials. Journal of Food Biochemistry. 2020. https://doi.org/10.1111/jfbc.13263
Drouin-Chartier JP, Chen S, Li Y, et al. Egg consumption and risk of cardiovascular disease: three large prospective US cohort studies, systematic review, and updated meta-analysis. BMJ. 2020. https://doi.org/10.1136/bmj.m513
Zhao B, Zhao B, Gan L, et al. Associations of Dietary Cholesterol, Serum Cholesterol, and Egg Consumption With Overall and Cause-Specific Mortality: Systematic Review and Updated Meta-Analysis. Circulation. 2022. https://doi.org/10.1161/circulationaha.121.057642
Shin JY, Xun P, Nakamura Y, He K. Egg consumption in relation to risk of cardiovascular disease and diabetes: a systematic review and meta-analysis. The American Journal of Clinical Nutrition. 2013. https://doi.org/10.3945/ajcn.112.051318
Zhong VW, Van Horn L, Cornelis MC, et al. Associations of Dietary Cholesterol or Egg Consumption With Incident Cardiovascular Disease and Mortality. JAMA. 2019. https://doi.org/10.1001/jama.2019.1572
Drouin-Chartier JP, Schwab AL, Chen S, et al. Egg consumption and risk of type 2 diabetes: findings from 3 large US cohort studies of men and women and a systematic review and meta-analysis of prospective cohort studies. The American Journal of Clinical Nutrition. 2020. https://doi.org/10.1093/ajcn/nqaa115
Mousavi SM, Zargarzadeh N, Rigi S, et al. Egg Consumption and Risk of All-Cause and Cause-Specific Mortality: A Systematic Review and Dose-Response Meta-analysis of Prospective Studies. Advances in Nutrition. 2022. https://doi.org/10.1093/advances/nmac040
US Food and Drug Administration. Egg Safety Final Rule. FDA. Content current as of 2022-08-10. https://www.fda.gov/food/egg-guidance-regulation-and-other-information/egg-safety-final-rule
Rona RJ, Keil T, Summers C, et al. The prevalence of food allergy: a meta-analysis. The Journal of Allergy and Clinical Immunology. 2007. https://doi.org/10.1016/j.jaci.2007.05.026

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