Eggs and cholesterol: what the trials found

The argument about eggs is quieter than it sounds. Eggs raise LDL cholesterol by about 7 mg/dL, and the same review that measured that found no link at all with cardiovascular events or with dying of any cause, and rated the whole body of evidence critically low in quality. The Nordic body that went through it set no upper limit for dietary cholesterol. The mechanism eggs usually get blamed through does not fire either. Pooling randomised trials, none of the three moved: choline, betaine and TMAO in the blood all stayed put. One thing here is settled and practical. Cook them. Cooked egg protein is about 91 percent digestible against about 51 percent raw. Most of what has been tested used 2 to 4 eggs a day, for anything from six hours to twelve weeks. That is well above what most people eat, so anyone quoting those trials at you is quoting a bigger dose than the one on your plate.

The numbers, per 100 g

How much is actually in it

• What is inside an egg is partly a decision made at the feed trough. Eggs enriched through hen feed reliably moved the matching blood markers in people, and reliably failed to show any health outcome beyond that. — 37 human intervention studies, most on eggs enriched with n-3 fatty acids, then carotenoid-enriched eggs, few on iodine (n = 37 studies) Evidence C source
  Fortified eggs generally improved biomarkers of the targeted nutrient, including circulating fatty acids, serum carotenoids and in a few studies urinary iodine. Evidence for downstream health outcomes was limited, inconsistent and hard to compare
• One medium egg carries about 200 mg of cholesterol, which is most of a Nordic day's intake in a single food. The body that reviewed this set no upper limit for dietary cholesterol at all. — Nordic and Baltic populations (n = огляд для NNR 2023) Evidence C source
  About 200 mg of cholesterol per medium egg, against average total cholesterol intakes of 230 to 400 mg a day in the Nordic countries and 250 to 340 in the Baltic. The Nordic Nutrition Recommendations set no upper intake level for dietary cholesterol

What a real portion looks like

• The argument about one egg a day is an argument about a portion most Europeans never reach. Average intake runs from 10 g a day in Iceland to 40 g in Latvia, against a medium egg of about 50 g. — adults in Iceland, Sweden, Finland, Norway, Denmark, Latvia, Estonia and Lithuania (n = національні обстеження восьми країн) Evidence C source
  Lowest means in Iceland (men 14, women 10 g/day) and Sweden (14 g/day). Finland, Norway and Denmark 23 to 28 g/day. Highest in Latvia (men 40, women 31 g/day)
• Across thirty-two trials, adding eggs to the diet did not change body weight, BMI, waist or lean mass, and where it did, the reason was the extra calories, not the egg. — adults in 32 controlled clinical trials (n = 32 trials (22 reporting weight, 13 BMI, 10 waist circumference, 4 fat-free mass)) Evidence A source
  No significant effect on body weight, BMI, waist circumference or fat-free mass overall; weight and BMI rose in trials longer than 12 weeks, in unhealthy participants, and where energy intake was not matched; BMI fell where the control group got another food or supplement, under calorie restriction, and in healthy subjects
• Every intervention trial on eggs and gut health used two to four eggs a day, which is well above what most people eat and is what the results actually describe. — 39,909 participants across 22 studies published 1998-2024, aged 18-85, from 11 countries; nine RCTs, three non-randomised trials, eight cross-sectional, two prospective cohorts (n = 39,909 participants across 22 studies) Evidence C source
  Intervention doses ranged from 2 to 4 whole eggs per day, durations from 6 hours to 12 weeks

What your body absorbs

• Eggs enriched with eye carotenoids delivered them into the bloodstream and then nothing happened: macular pigment did not rise and vision did not improve. — healthy adults, mean age 41 in the enriched group and 35 in the control group (n = not stated in the abstract; full text retrieved) Evidence B source
  Serum lutein, zeaxanthin and meso-zeaxanthin rose significantly more in the enriched group (P < 0.001 for each); no significant increase in macular pigment and no significant improvement in visual performance in either group; total cholesterol rose in both groups but stayed within the normative range

What cooking and storage change

• Raw eggs are about half as digestible as cooked ones. The trial that tested the Rocky breakfast quotes the figures: roughly 91 percent for cooked egg protein against roughly 51 percent for raw. — cited figures come from earlier work by Evenepoel and colleagues, not from this trial's own participants (n = цифри травності взяті з попередніх робіт, не з цього випробування) Evidence B source
  Cooked eggs about 91% digestible against about 51% for raw. The authors attribute the gap to heat denaturing ovalbumin and ovotransferrin and partly inactivating trypsin inhibitors
• Worse digestion did not mean worse muscle. Five raw eggs and five boiled eggs after a workout built muscle protein at the same rate, even though the boiled ones put 20 percent more amino acids into the blood. — 45 healthy resistance-trained young men, mean age 24, randomised to 5 raw eggs, 5 boiled eggs, or a control breakfast of about 5 g protein (n = 45 men) Evidence B source
  Peak plasma essential amino acids 20% higher after boiled eggs (P < 0.001). Myofibrillar protein synthesis 0.067%/h after raw and 0.065%/h after boiled against 0.056%/h on the control breakfast, with no significant difference between the egg groups (P = 0.077)
• The reason an American egg must live in the fridge and a European one need not is the washing: once the cuticle is off, a cold egg warming up on the counter draws bacteria inward. — US retail shell eggs Evidence E source
  US eggs are washed and sanitised at the plant and must then be held at 40 °F or below; egg-containing dishes are to be cooked to an internal 160 °F

Safety, limits and interactions

• Eggs are blamed for raising TMAO, the compound linked to heart disease. Pooling the randomised trials, they do not: choline goes up, TMAO does not move. — 6 randomised controlled trials, 5 of them reporting betaine and TMAO (n = 6 trials) Evidence A source
  No overall effect on choline (WMD 0.10, 95% CI -0.92 to 1.12), betaine (0.21, -8.50 to 8.92) or TMAO (-0.08, -0.47 to 0.32). Heterogeneity above 85% for choline and betaine but only 23% for TMAO
• A second review, working from different studies, landed in the same place: eggs raised blood choline and left TMAO and C-reactive protein where they were. — healthy adults in 9 randomised trials, 3 non-randomised intervention trials, 8 cross-sectional studies and 2 prospective cohorts (n = 22 studies, 10 in the meta-analyses) Evidence A source
  Plasma choline rose (n = 5, p < 0.001) over four weeks or less. TMAO did not change (n = 6, p = 0.22) and neither did C-reactive protein (n = 3, p = 0.45)

What people believe that the data does not support

• Eggs raise LDL cholesterol by about 7 mg/dL and show no link at all to cardiovascular events or to dying of anything. Both halves of that sentence come from the same review. — 14 meta-analyses, 10 of observational studies and 4 of intervention studies (n = 14 meta-analyses) Evidence A source
  LDL cholesterol weighted mean difference 7.39 mg/dL (95% CI 5.82 to 8.95), total cholesterol 9.12, apolipoprotein B-100 0.06, HDL 1.37 upward. No association found for any cardiovascular outcome or for all-cause mortality between high and low egg intake
• When a trial separated the two things an egg brings, only one of them raised LDL. Two eggs a day inside a low saturated fat diet lowered LDL, and an egg free diet high in saturated fat did not. — 61 adults aged 39 on average with baseline LDL below 3.5 mmol/L. 54 completed at least one phase and 48 completed all three (n = 61 randomised, 48 completed all phases) Evidence B source
  LDL 103.6 on the two egg low saturated fat diet against 109.3 on control (P = 0.02), and 107.7 on the egg free high saturated fat diet (P = 0.52). Across all diets saturated fat correlated with LDL (beta 0.35, P = 0.002) and dietary cholesterol did not (beta -0.006, P = 0.42)
• The mechanism eggs are usually blamed through does not fire: pooling randomised trials, eating eggs moved neither choline, nor betaine, nor TMAO in the blood. — adults in six randomised controlled trials (six contributing choline, five betaine and TMAO) (n = 6 RCTs) Evidence A source
  Choline WMD 0.10 (95% CI -0.92 to 1.12; p = 0.847); betaine WMD 0.21 (95% CI -8.50 to 8.92; p = 0.962); TMAO WMD -0.08 (95% CI -0.47 to 0.32; p = 0.692)

Who this works differently for

• Giving a baby egg between four and twelve months of age cut the risk of egg allergy by about 40 percent. The old advice to wait was the thing causing harm. — 12 randomised trials of introducing allergenic food before 12 months of age. The egg analysis pooled 8 trials (n = 8 trials, 5193 participants for the egg outcome) Evidence A source
  Egg allergy risk ratio 0.58 (95% CI 0.44 to 0.78), high to moderate certainty. Multiple food allergies 0.49 (0.33 to 0.74), peanut 0.31 (0.17 to 0.54), eczema 0.88 (0.78 to 1.00)
• Whether eggs help an ageing brain rests on eleven studies, only one of which fed anybody anything. — healthy adults, predominantly older, more than 38,000 participants (n = 11 studies: 1 pre-post intervention, 6 prospective cohorts, 3 cross-sectional, 1 case-control) Evidence C source
  Two studies reported reduced risk of dementia or cognitive impairment with moderate egg consumption; outcomes spanned global cognition, memory, executive function, language, processing speed and dementia risk
• Baked-egg ladders bring most allergic children to tolerance, but the reviewers will not say the ladder is what caused it. — children with IgE-mediated cow's milk or egg allergy, from 9946 titles screened (n = 29 studies) Evidence A source
  Tolerance in 69% on the egg ladder, 49% on baked egg oral immunotherapy; all-severity allergic reactions in 21% and 20% respectively, epinephrine used in 3% of egg-ladder patients; mean time to tolerance 13.25 months for baked egg and 19.1 months for baked egg OIT

What is still unknown

• After forty years of argument, the honest summary of the egg evidence is that it is too weak to argue with. The reviewers stop short of telling anyone to eat fewer eggs because nothing supports doing so. — 14 meta-analyses of egg consumption and health outcomes (n = 14 meta-analyses) Evidence A source
  The wide range of outcomes, substantial variability and high heterogeneity were judged to indicate a lack of robust evidence, and the overall quality of studies was critically low
• Above one egg a day the evidence simply stops. The people who eat three eggs for breakfast are outside every dataset anyone has reviewed. — European populations (n = огляд для NNR 2023) Evidence C source
  Limited evidence suggests up to one egg a day is not associated with increased cardiovascular risk, and there are little data on health effects of intakes above one egg a day
• The most common everyday complaint about eggs, that they sit heavily, has never been studied: of twenty-two studies on eggs and the gut, not one measured gut symptoms. — 39,909 participants across 22 studies in healthy adults (n = 22 studies; TMAO measured in 16, plasma choline in 12, microbiome in 8, inflammatory markers in 5, faecal short-chain fatty acids in 1) Evidence C source
  No study measured gastrointestinal symptoms at all

The bottom line

Cook your eggs. That is the instruction on this page with the least argument behind it. Boiled eggs put about 20 percent more amino acids into the blood than raw ones, although in young trained men both built muscle at the same rate, so the raw egg breakfast buys worse digestion and no visible gain. A medium egg carries about 200 mg of cholesterol, most of a typical Nordic day in one food, and the body that reviewed that still set no upper limit. When one trial separated the two things an egg brings, saturated fat tracked with LDL and dietary cholesterol did not. Two popular reasons for eating more eggs did not survive testing. Across 32 trials, eggs changed nothing in body weight, BMI, waist or lean mass, and eggs enriched with eye carotenoids delivered those carotenoids into the blood while macular pigment and visual performance stayed exactly where they were. What eggs do to an ageing brain rests on eleven studies, only one of which fed anybody anything. The everyday complaint we hear most, that eggs sit heavily, has never been studied at all: of 22 studies on eggs and the gut, not one measured gut symptoms. Salmonella is a gap of the same shape on our side. Our corpus holds no pooled analysis of eggs and salmonella, only the handling rule, and that rule turns on washing. An American egg has had its cuticle washed off and has to stay cold, because a cold egg left out to warm up sweats, and that moisture carries bacteria inward. A European egg is unwashed and does not. For babies the old advice has turned around completely: egg given between four and twelve months cut the risk of egg allergy by about 40 percent. If your child already reacts to egg, the baked-egg ladder is a different question. Most children on one reach tolerance, and the reviewers rate the certainty very low and will not say the ladder is what caused it. Make that one with your paediatrician rather than alone.

Sources

1. egg-e3-08 · scoping review of human intervention studies
   Across studies, fortified egg consumption was generally associated with improvements in intake estimates and biomarkers of targeted nutrient status, including circulating fatty acids, serum carotenoids, and, in a limited number of studies, urinary iodine.
   Nutrients, 2026 · checked 2026-09-18
2. egg-e3-09 · scoping review for a national nutrition recommendation
   One medium-sized egg contains approximately 200 mg of cholesterol. The average total cholesterol intake in the Nordic countries is 230–400 mg/day and 250–340 mg/day in the Baltic countries (1).
   Food & Nutrition Research, 2024, огляд для Nordic Nutrition Recommendations 2023 · checked 2026-09-18
3. egg-e3-10 · compilation of national dietary surveys
   The lowest reported mean egg intakes are in Iceland (men: 14 g/day and women: 10 g/day) and Sweden (14 g/day in both men and women), whereas in Finland, Norway, and Denmark, the mean intakes in men range between 24 and 28 g/day and in women between 23 and 24 g/day.
   Food & Nutrition Research, 2024, огляд для Nordic Nutrition Recommendations 2023 · checked 2026-09-18
4. eggs-b-03 · meta-analysis of clinical trials
   The analyses revealed that whole egg consumption has no significant effect on body weight (n = 22), BMI (n = 13), WC (n = 10), and FFM (n = 4, P > 0.05).
   Systematic Reviews, 2023 · checked 2026-09-21
5. eggs-b-04 · systematic review with meta-analyses
   For the intervention trials, the interventions ranged in dose from 2 to 4 whole eggs/day and duration from 6 h to 12 weeks.
   Nutrients, 2025 · checked 2026-09-21
6. eggs-b-02 · single-blind placebo-controlled trial
   There was no significant increase in MP in either study group post intervention, and we saw no significant improvement in visual performance in either group.
   Nolan et al., British Journal of Nutrition, 2017 · checked 2026-09-21
7. egg-e3-03 · randomised controlled trial, discussion citing prior digestibility studies
   These results are in line with previous pioneering work by Evenepoel et al. (2, 3), who showed that cooked eggs have a much higher digestibility (∼91%) when compared with raw eggs (∼51%).
   Hermans et al., Journal of Nutrition, 2022 · checked 2026-09-18
8. egg-e3-04 · randomised controlled trial
   The ingestion of raw, as opposed to boiled, eggs attenuates the postprandial rise in circulating EAA concentrations. However, postexercise muscle protein synthesis rates do not differ after ingestion of 5 raw compared with 5 boiled eggs in healthy young men.
   Hermans et al., Journal of Nutrition, 2022 · checked 2026-09-18
9. eggs-b-08 · agency food-safety guidance
   A cold egg left out at room temperature can sweat, facilitating the movement of bacteria into the egg.
   Shell Eggs from Farm to Table, USDA Food Safety and Inspection Service · checked 2026-09-21
10. egg-e3-05 · systematic review and meta-analysis of randomised controlled trials
    No significant overall effects were observed for choline (WMD = 0.10; 95% CI: - 0.92 to 1.12; p = 0.847), betaine (WMD = 0.21; 95% CI: - 8.50 to 8.92; p = 0.962), or TMAO (WMD = - 0.08; 95% CI: - 0.47 to 0.32; p = 0.692).
    Nutrition Journal, 2025 · checked 2026-09-18
11. egg-e3-06 · systematic review and meta-analysis
    Meta-analyses indicated that egg consumption did not impact plasma TMAO (n = 6, p = 0.22) or CRP (n = 3, p = 0.45) concentrations but did increase plasma choline (n = 5, p < 0.001) in the short term (≤4 weeks).
    Nutrients, 2025 · checked 2026-09-18
12. egg-e3-01 · umbrella review of systematic reviews and meta-analyses
    The level of evidence was very weak for all the significant associations: risk of heart failure (RR 1.15; 95%CI: 1.02-1.30), cancer mortality (RR 1.13; 95%CI 1.06-1.20), higher levels of LDL cholesterol (WMD 7.39; 95%CI 5.82-8.95), total cholesterol (WMD 9.12; 95%CI 7.35-10.89), and apolipoprotein B-100 (WMD 0.06; 95%CI 0.03-0.08).
    Nutrition, Metabolism and Cardiovascular Diseases, 2025 · checked 2026-09-18
13. egg-e3-12 · randomised controlled crossover feeding trial
    Across all diets, saturated fat intake was positively correlated with LDL cholesterol (β = 0.35, P = 0.002), whereas dietary cholesterol was not (β = -0.006, P = 0.42).
    Nutting et al., American Journal of Clinical Nutrition, 2025 · checked 2026-09-18
14. eggs-b-01 · meta-analysis of randomised controlled trials
    No significant overall effects were observed for choline (WMD = 0.10; 95% CI: - 0.92 to 1.12; p = 0.847), betaine (WMD = 0.21; 95% CI: - 8.50 to 8.92; p = 0.962), or TMAO (WMD = - 0.08; 95% CI: - 0.47 to 0.32; p = 0.692).
    Nutrition Journal, 2025 · checked 2026-09-21
15. egg-e3-07 · systematic review and meta-analysis of randomised controlled trials
    We found high to moderate certainty evidence suggested that early introduction of allergen-containing foods reduces the risk of multiple food allergies (4 RCTs, 3854 participants, RR 0.49, 95% CI 0.33 to 0.74), egg (8 RCTs, 5193 participants, RR 0.58, 95% CI 0.44 to 0.78), peanut (3 RCTs, 4183 participants, RR 0.31, 95% CI 0.17 to 0.54) and atopic dermatitis or eczema (4 RCTs, 3579 participants, RR 0.88, 95% CI 0.78 to 1.00).
    BMJ Evidence-Based Medicine, 2024 · checked 2026-09-18
16. eggs-b-06 · systematic review, narrative synthesis
    Eleven studies met the inclusion criteria: one pre-post intervention study, six prospective cohort studies, three cross-sectional studies, and one case-control study.
    Journal of Nutrition, Health and Aging, 2025 · checked 2026-09-21
17. eggs-b-07 · meta-analysis of intervention studies
    There is very low certainty of evidence supporting DAT safety and efficacy. We cannot conclude that DAT accelerates tolerance development.
    Journal of Allergy and Clinical Immunology: In Practice, 2024 · checked 2026-09-21
18. egg-e3-02 · umbrella review of systematic reviews and meta-analyses
    Due to the critically low strength of studies, insufficient evidence is available to discourage egg consumption, suggesting eggs can be part of a healthy diet.
    Nutrition, Metabolism and Cardiovascular Diseases, 2025 · checked 2026-09-18
19. egg-e3-11 · scoping review for a national nutrition recommendation
    There are little data on health effects of intakes above one egg/day.
    Food & Nutrition Research, 2024, огляд для Nordic Nutrition Recommendations 2023 · checked 2026-09-18
20. eggs-b-05 · systematic review
    Most studies measured TMAO concentrations (n = 16), followed by plasma choline (n = 12), gut microbiome composition and diversity (n = 8), circulating inflammatory markers (n = 5), and faecal SCFAs (n = 1). No studies explored other relevant outcomes, such as gut symptoms.
    Nutrients, 2025 · checked 2026-09-21