Updated: Nov 12, 2020
Eggs are high in saturated fats and dietary cholesterol and have been associated with increased risks for heart disease, diabetes, colorectal cancer and prostate cancer.
Around 60% of calories from eggs come from fat - big portion of which is from saturated fat.
Breakdown on Cholesterol
You do not need cholesterol in your diet as your body is more than capable of making enough to meet the body’s needs.
Dietary cholesterol does impact your blood cholesterol levels. The effect the dietary cholesterol has depends on our diet. If our diet is already high in cholesterol and saturated fat, adding more cholesterol does not have as much effect. However, when it is added to a healthy diet low in dietary cholesterol, the blood cholesterol levels do increase, especially LDL cholesterol (bad cholesterol).
HDL’s function is more important than just the levels. HDL (good cholesterol) is supposed to be anti-inflammatory but when diet is high in saturated fats, it can become pro-inflammatory.
Foods high in cholesterol like eggs can promote LDL oxidation and increase cardiovascular disease risk.
The saturated fat and cholesterol from eggs play a role in the connection between eggs and heart disease. High blood cholesterol levels lead to thickening of walls of blood vessels which restrict blood flow to organs like the heart and the brain. Eggs also contain choline which in our body gets converted to a toxic compound called TMAO (trimethylamine oxidase), which increases the risk for heart attack and stroke. A review looking at 14 research studies found people consuming eggs frequently had higher risk for heart disease and stroke. A study found people eating one egg a day (or seven eggs a week) to have an 80% higher coronary artery calcium scores, a measure of heart disease risk.
High cholesterol is also associated with other health problems such as breast cancer, inflammation, joint pain and infertility. Furthermore, when consuming foods high in cholesterol, you're consuming saturated fat and saturated fat itself increases cholesterol levels increasing risks for worse health outcomes over long-term.
Egg consumption has also been linked to higher diabetes risk as it contributes to higher levels of cholesterol and saturated fat. A diet high in saturated fat increases insulin resistance, since saturated fat can interfere with insulin's ability to transport glucose into cells from blood. Egg consumption has also been found to increase risk for gestational diabetes.
Consumption of eggs may also increase risk for certain cancers including breast, colon, prostate, rectal and bladder. It has been suggested that TMAO (described above) promotes the growth of cancer, especially in breast, prostate and ovary cancer. Only consuming 1.5 eggs per week has been shown to increase the risk for colon cancer by five times. Even moderate consumption of eggs may triple the risk of bladder cancer. A 2011 Harvard study found that egg consumption to have a link with prostate cancer as well. Only 2.5 eggs per week showed men to increase their risk of lethal form of prostate cancer by 81% in comparison with men who consumed less than half an egg per week. The possible explanation is the high amounts of cholesterol and choline in eggs.
People often switch to egg whites to lower their intake of cholesterol and saturated fat while hoping to increase their protein intake. High protein, especially from animal protein, has been linked to higher risk of mortality and various diseases including certain cancers, kidney disease and kidney stones. Egg whites are not necessary to meet protein requirements. Plant based protein options like legumes, whole grains, nuts, seeds and even some vegetables not only add protein to your diet but also fiber, antioxidants, phytochemicals, vitamins and minerals, which all promote health.
Egg Substitutes graphic for cooking and baking can be found here. Also, check out the chickpea omelette recipe and the tofu scramble recipe.
Freeman AM, Morris PB, Barnard N, Esselstyn CB, Ros E, Agatston A, Devries S, O'Keefe J, Miller M, Ornish D, Williams K, Kris-Etherton P. Trending Cardiovascular Nutrition Controversies. J Am Coll Cardiol. 2017 Mar 7;69(9):1172-1187.
Spence JD, Jenkins DJ, Davignon J. Dietary cholesterol and egg yolks: not for patients at risk of vascular disease. Can J Cardiol. 2010 Nov;26(9):e336-9.
Spence JD, Jenkins DJ, Davignon J. Egg yolk consumption and carotid plaque. Atherosclerosis. 2012 Oct;224(2):469-73.
Briel M, Ferreira-Gonzalez I, You JJ, Karanicolas PJ, Akl EA, Wu P, Blechacz B, Bassler D, Wei X, Sharman A, Whitt I, Alves da Silva S, Khalid Z, Nordmann AJ, Zhou Q, Walter SD, Vale N, Bhatnagar N, O'Regan C, Mills EJ, Bucher HC, Montori VM, Guyatt GH. Association between change in high density lipoprotein cholesterol and cardiovascular disease morbidity and mortality: systematic review and meta-regression analysis. BMJ. 2009 Feb 16;338:b92.
Navab M, Reddy ST, Van Lenten BJ, Fogelman AM. HDL and cardiovascular disease: atherogenic and atheroprotective mechanisms. Nat Rev Cardiol. 2011 Apr;8(4):222-32.
Kosmas CE, Martinez I, Sourlas A, Bouza KV, Campos FN, Torres V, Montan PD, Guzman E. High-density lipoprotein (HDL) functionality and its relevance to atherosclerotic cardiovascular disease. Drugs Context. 2018 Mar 28;7:212525.
Nicholls SJ, Lundman P, Harmer JA, Cutri B, Griffiths KA, Rye KA, Barter PJ, Celermajer DS. Consumption of saturated fat impairs the anti-inflammatory properties of high-density lipoproteins and endothelial function. J Am Coll Cardiol. 2006 Aug 15;48(4):715-20.
Wang F, Zheng J, Yang B, Jiang J, Fu Y, Li D. Effects of Vegetarian Diets on Blood Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Am Heart Assoc. 2015 Oct 27;4(10):e002408.
Li Y, Zhou C, Zhou X, Li L. Egg consumption and risk of cardiovascular diseases and diabetes: a meta-analysis. Atherosclerosis. 2013;229:524- 530.
Clarke R, Frost C, Collins R, Appleby P, Peto R. Dietary lipids and blood cholesterol: quantitative meta-analysis of metabolic ward studies. BMJ. 1997;314:112-117.
Howell WH, McNamara DJ, Tosca MA, Smith BT, Gaines JA. Plasma lipid and lipoprotein responses to dietary fat and cholesterol: a meta-analysis. Am J Clin Nutr. 1997;65:1747-1764.
Hopkins PN. Effects of dietary cholesterol on serum cholesterol: a metaanalysis and review. Am J Clin Nutr. 1992;55:1060-1070.
Levin S, Wells C, Barnard N. Dietary cholesterol and blood cholesterol concentrations. JAMA. 2015;314:2083-2084.
Berger S, Raman G, Vishwanathan R, Jacques PF, Johnson EJ. Dietary cholesterol and cardiovascular disease: a systematic review and meta-analysis. Am J Clin Nutr. 2015;102:276-294.
Tang WH, Wang Z, Levison BS, et al. Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk. N Engl J Med. 2013;368:1575- 1584.
Li C, Yang L, Zhang D, Jiang W. Systematic review and meta-analysis suggest that dietary cholesterol intake increases risk of breast cancer. Nutr Res. 2016;36:627-635.
Potluri R, Lavu D, Uppal H, Chandran S. Hyperlipidaemia as a risk factor for breast cancer? Report presented at; European Society of Cardiology 2014 Frontiers in Cardiovascular Biology Meeting; July 4, 2014: Barcelona, Spain.
Tilley BJ, Cook JL, Docking SI, Gaida JE. Is higher serum cholesterol associated with altered tendon structure or tendon pain? A systematic review. Br J Sports Med. 2015;49:1504-1509.
Schisterman EF, Mumford SL, Browne RW, Barr DB, Chen Z, Louis GMB. Lipid concentrations and couple fecundity: the LIFE study. J Clin Endocrinol Metab. 2014;99:2786-2794.
Zong G, Li Y, Wanders AJ, et al. Intake of individual saturated fatty acids and risk of coronary heart disease in US men and women: two prospective longitudinal cohort studies. BMJ. 2016;355:i5796-i5807
Estadella D, da Penha Oller do Nascimento CM, Oyama LM, Ribeiro EB, Dâmaso AR, de Piano A. Lipotoxicity: effects of dietary saturated and transfatty acids. Mediators Inflamm. 2013;2013:137579-137593.
Schrauwen P. High-fat diet, muscular lipotoxicity and insulin resistance. Proc Nutr Soc. 2007;66:33-41.
Djoussé L, Khawaja OA, Gaziano JM. Egg consumption and risk of type 2 diabetes: a meta-analysis of prospective studies. Am J Clin Nutr. 2016;103:474-480.
Djoussé L, Gaziano JM. Egg consumption in relation to cardiovascular disease and mortality: the Physicians’ Health Study. Am J Clin Nutr. 2008;87:964-969.
Qiu C, Frederick IO, Zhang C, et al. Risk of gestational diabetes mellitus in relation to maternal egg and cholesterol intake. Am J Epidemiol. 2011;173:649-658.
Keum N, Lee DH, Marchand N, et al. Egg intake and cancers of the breast, ovary and prostate: a dose-response meta-analysis of prospective observational studies. Br J Nutr. 2015;114:1099-1107.
Tse G, Eslick GD. Egg consumption and risk of GI neoplasms: doseresponse meta-analysis and systematic review. Eur J Nutr. 2014;53:1581- 1590.
Miller CA, Corbin KD, da Costa KA, et al. Effect of egg ingestion on trimethylamine-N-oxide production in humans: a randomized, controlled, dose-response study. Am J Clin Nutr. 2014;100:778-786.
Iscovich JM, L’Abbe KA, Castelleto R, et al. Colon cancer in Argentina. I: risk from intake of dietary items. Int J Cancer. 1992;51:851-857.
Zhang J, Zhao Z, Berkel HJ. Egg consumption and mortality from colon and rectal cancers: an ecological study. Nutr Cancer. 2003;46:158-165.
Radosavljevic V, Jankovic S, Marinkovic J, Dokic M. Diet and bladder cancer: a case-control study. Int Urol Nephrol. 2005;37:283-289.
Richman EL, Kenfield SA, Stampfer MJ, et al. Egg, red meat, and poultry intake and risk of lethal prostate cancer in the prostate specific antigenera: incidence and survival. Cancer Prev Res. 2011;4:2110-2121.
Reddy ST, Wang CY, Sakhaee K, et al. Effect of low-carbohydrate high-protein diets on acid-base balance, stone-forming propensity, and calcium metabolism. Am J Kidney Dis. 2002;40:265-274.
Fontana L, Klein S, Holloszy JO. Long-term low-protein, low-calorie diet and endurance exercise modulate metabolic factors associated with cancer risk. Am J Clin Nutr. 2006;84:1456-1462.
Levine ME, Suarez JA, Brandhorst S, et al. Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population. Cell Metab. 2014;19:407-417.