There have been countless debates regarding the health impact of regular egg consumption. While research has shown that consumption of the food product for breakfast can lead to increased weight loss, recent evidence shows that eating three eggs per week can increase the risk of early mortality.

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Are Eggs Good for Heart Health?

There has been on-going debate regarding the impact of the regular consumption of eggs on the cardiovascular system. Currently, there is conflicting literature relating to the relationship between egg consumption, cholesterol, and the prevalence of coronary heart disease (CHD).

Based on a 2017 study, there was a consensus that eggs were safe for the heart. This aligned with guidance from the Dietary Guidelines for America, who noted that the link between cardiovascular disease and dietary cholesterol was minimal.

The guidelines were based on the fact that the association between egg-derived cholesterol and other food products containing “bad” cholesterol and CHD was considered less significant compared to the well-supported impact of saturated fat on low-density lipoprotein cholesterol – a key risk factor for atherosclerosis.

However, more recent research has found that eating a minimum of three eggs per week can increase the likelihood of early death.

A team of researchers from the Department of Preventive Medicine at Northwestern University presented evidence that eating three eggs per week or 300 milligrams or more of cholesterol per day can increase the risk of death.

A single large egg contains approximately 186 milligrams of cholesterol. Meaning those who eat on average three large eggs within a meal would be consuming approximately 558 milligrams of cholesterol.

The study followed over 29,000 participants for 17 years. During the research, 5400 cardiovascular events were recorded, comprised of 113 fatalities caused by heart disease, 1897 cases of heart disease, and 1302 cases of stroke. Six thousand one hundred thirty-two of the participants died from other non-cardiovascular-related causes.

Data analysis revealed that consuming an extra 300 milligrams of cholesterol per day was linked to a 3.2% increased risk of developing heart disease in addition to a 4.4% increased risk of dying early due to any cause.

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The authors noted that the results serve as a reminder that eggs, especially the yolk, contain cholesterol which can cause adverse health consequences.

Therefore, to reduce the risk of CHD, less cholesterol should be consumed. However, as a purely observational study, other factors could have influenced the data.

The data also contrasts against literature outlining the benefits of egg consumption on several health parameters, including weight management and eye health.

Eggs and Weight Loss

Eggs are considered to provide an essential source of protein for humans. They compare favorably to other protein sources, being only inferior to breast milk. The yolk protein, in particular, has been reported to have larger satiety effects compared to other isocaloric foods with lower levels of satiety.

Research examining the impact of low satiety and high satiety meals of the same caloric content on weight loss found participants consumed fewer calories after eating a breakfast containing eggs.

Those consuming the egg and bagel breakfast lost more weight after eight weeks. Similar research has found that those consuming the same breakfast without the egg component were less satiated, hungrier, and had higher insulin levels three hours after eating.

Based on this evidence, consuming eggs as part of breakfast may have positive effects on those wishing to lose weight through the reduction of calorie intake.  

Nutritional Components

Eggs are relatively cheap, yet highly nutritious food products that boast a plethora of nutrients essential for human health. One egg contains plenty of vitamins, minerals, fats, essential proteins, and bioactive compounds and hosts favorable nutrient to energy density ratios.

Macronutrient-wise, eggs contain many essential vitamins, including vitamin A, vitamin B12, vitamin, D, riboflavin, and folate, alongside a range of minerals such as sodium, iron, calcium, and potassium.

Eye Health

The pigments responsible for giving egg yolks their yellow/orange color have received interest due to their role in eye health.

Carotenoids – the pigment responsible – is comprised of lutein and zeaxanthin which are unable to be synthesized by the human body and require dietary intake.

The pigments are also found in the yellow spot of the retina, which improves the clarity of vision, protects the macula from blue light damage, and removes reactive oxygen species.

Eating foods containing carotenoids has been associated with the reduced likelihood of developing several ocular conditions, including cataracts and age-related macular degeneration.

References and Further Reading

• Eckel, R.H., (2019). Reconsidering the importance of the association of egg consumption and dietary cholesterol with cardiovascular disease risk. Jama, 321(11), pp.1055-1056. Doi: 10.1001/jama.2019.1850
• Dietary Guidelines Advisory Committee. (2015). Scientific Report of the 2015 Dietary Guidelines Advisory Committee: Advisory Report to the Secretary of Health and Human Service and the Secretary of Agriculture. Washington, DC: US Dept of Agriculture, Agricultural Research Service.
• Zhong, V.W., Van Horn, L., Cornelis, M.C., Wilkins, J.T., Ning, H., Carnethon, M.R., Greenland, P., Mentz, R.J., Tucker, K.L., Zhao, L. and Norwood, A.F. (2019). Associations of dietary cholesterol or egg consumption with incident cardiovascular disease and mortality. Jama, 321(11), pp.1081-1095. Doi: 10.1001/jama.2019.1572
• Kuang, H., Yang, F., Zhang, Y., Wang, T. and Chen, G. (2018). The impact of egg nutrient composition and its consumption on cholesterol homeostasis. Cholesterol, 2018. Doi: 10.1155/2018/6303810
• Vander Wal, J.S., Marth, J.M., Khosla, P., Jen, K.C. and Dhurandhar, N.V. (2005). Short-term effect of eggs on satiety in overweight and obese subjects. Journal of the American College of Nutrition, 24(6), pp.510-515. https://doi.org/10.1080/07315724.2005.10719497
• Ratliff, J. and Leite, J.O., 2010. de Ogburn R, Puglisi MJ, VanHeest J, Fernandez ML. (2010). Consuming eggs for breakfast influences plasma glucose and ghrelin, while reducing energy intake during the next 24 h in adult men. Nutr Res, 30, pp.96-103. Doi: 10.1016/j.nutres.2010.01.002
• Vander Wal, J. S., Gupta, A., Khosla, P., & Dhurandhar, N. V. (2008). Egg breakfast enhances weight loss. International Journal of obesity, 32(10), 1545-1551. https://doi.org/10.1038/ijo.2008.130.
• Seddon, J. M., Ajani, U. A., Sperduto, R. D., Hiller, R., Blair, N., Burton, T. C., … & Yannuzzi, L. A. (1994). Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular degeneration. Jama, 272(18), 1413-1420. 10.1001/jama.1994.03520180037032