Does Egg Consumption Increase Risk for Developing Heart Disease?

ImageAfter a colleague asked my opinion on the relationship between egg consumption and cardiovascular disease, I decided to delve further into the topic.

For decades, we’ve been advised to limit egg consumption to reduce our risk of developing heart disease. The reasoning for this is based on the diet-heart hypothesis, which argues eating foods rich in cholesterol and saturated fat increases risk of developing heart disease. Specifically applied to eggs, the argument states: 1) eggs are rich in cholesterol; 2) eating cholesterol has been shown, in some studies, to increase serum cholesterol; 3) high serum cholesterol promotes heart disease. Using this logic, populations with increased egg consumption should have increased rates of heart disease. 

First, let’s address the issue of egg consumption and cholesterol. Does eating eggs, which are high in cholesterol, increase serum cholesterol?

One experimental feeding study found a modest increase in serum cholesterol (1-3%) from eating one additional egg per day[1]. However, larger studies found conflicting results.

The Framingham Heart Study compared cholesterol levels of individuals eating the most and least eggs. When comparing the men with highest egg consumption to those with the lowest, there was no difference in serum cholesterol. Women eating the most eggs actually had slightly lower cholesterol than women eating the least eggs[2].

Similarly, the Multiple Risk Factor Intervention Trial found that individuals with cholesterol lower than 200 ate more eggs than individuals with cholesterol greater than 220[3].

Once again, the Third National Health and Nutrition Examination Survey of more than 20,000 participants found that participants eating less than one egg per week had higher serum cholesterol than participants eating more than four eggs per week[4].

Thus, the hypothesis that egg consumption actually increases serum cholesterol is, at best, tenuous. The more important question is does egg consumption actually affect heart disease risk?

A study of 26,000 California Seventh-Day Adventists found no increase in coronary heart events in participants eating the most eggs versus those eating the least[5]. A study of 5,000 Finish men and women found no effect of egg consumption on death rate from coronary heart disease[6]. The Fakuoka Heart Study examined 660 heart attack patients and found no association between egg consumption and heart attack risk[7]. An Italian case-controlled study found no effect of egg consumption on heart attack risk[8].

The best study to specifically examine the relationship between egg consumption and coronary heart disease followed 117,000 men and women for 8-14 years, tracking their egg consumption and health outcomes[9]. Compared to those eating less than one egg per week, individuals eating more than seven eggs per week had no increase in coronary heart disease.

Finally, one study examined the relationship between egg consumption and stroke in 37,000 Japanese men and women[10]. Surprisingly, those with daily egg consumption had a 30% reduced rate of stroke compared to individuals who never ate eggs.

In summary, the data does not indicate eggs have a negative impact on heart health. After a long campaign against egg consumption, the American Heart Association gave up the fight in 2000. They still promote limiting cholesterol to less than 300 mg/day (eggs have about 280 mg), but no longer specifically warn against egg consumption.

After looking at the data, I was surprised by the complete lack of association between egg consumption and heart disease. Eggs are exactly the type of food (high in cholesterol and saturated fat) we’ve been told not to eat for decades. Perhaps it’s time to re-evaluate the validity of the diet-heart hypothesis and examine alternative hypotheses that incorporate this new data.

[1] McNamara DJ. (2000) The impact of egg limitations on coronary disease risk: do the numbers add up? Jour Am Coll Nutr. 19:540S-548S.

[2] Dawber TR, Nickerson RJ, Brand FN, Pool J. (1982) Eggs, serum cholesterol, and coronary heart disease. Am Jour Clin Nutr. 36:617-625.

[3] Tillotson JL, Bartsch GE, Gorder D, Grandits GA, Stamler J. (1997) Food group and nutrient inakes at baseline in the Multiple Risk Factor Intervention Trial. Am Jour Clin Nutr. 65:228S-257S.

[4] Song WO, Kerver JM. (2000) Nutritional contribution of eggs to American Diets. Jour Am Coll Nutr. 19:556S-562S.

[5] Fraser GE. (1999) Associations between diet and cancer, ischemic heart disease, and all-cause mortality in non-Hispanic white California Seventh-day Adventists. Am Jour Clin Nutr. 70:532S-538S.

[6] Knekt P, Reunanen A, Jarvinen R, et al. (1994) Antioxidant vitamin intake and coronary mortality in a longitudinal population study. Am Jour Epidemiol. 139:1180-1189.

[7] Sasazuki S. (2001). Case-control study of nonfatal myocardial infarction in relation to selected foods in Japanese men and women. Jpn Circ Jour. 65:200-206.

[8] Gramenzi A, Gentile A, Fasoli M, et al. (1990) Association between certain foods and risk of acute myocardial infarction in women. BMJ. 300:771-773.

[9] Hu FB, Stampfer MJ, Rimm EB, et al. (1999) A prospective study of egg consumption and risk of cardiovascular disease in men and women. JAMA. 281: 1387-1394.

[10] Sauvaget C, Nagano J, Allen N. (2003) Intake of animal products and stroke mortality in the Hiroshima/Nagasaki Life Span Study. Int Jour Epidemiol. 32: 536-43.

8 thoughts on “Does Egg Consumption Increase Risk for Developing Heart Disease?

  1. Bill, Thanks for posting this and for compiling the various research. I wanted to ask, in any of that research does anyone distinguish between “factory farm,” commercial eggs versus organic, truly pastured chickens and their eggs? I would think very similar to all the studies that led to the USDA, AHA etc., in making claims/recommendations to limit saturated fats, when there is little or no distinction between bad fats (hydrogenated vegetable oils, animal fats from sick animals) versus healthy saturated fats such as coconut oil, olive oil, real butter from grass fed, healthy animals.

    Anyway, just a thought that always bugs me about the research and claims. Thanks for your research.

    • Hi Lon, none of these studies specifically looked at differences between commercial eggs vs organic. There was probably quite a bit of variability of egg origin/chicken housing between studies because the studies took place in different countries between the 1970’s and early 2000’s. For example, one study was in California, two were in Japan, one in Finland, one in Italy, etc. It’s interesting the data is consistent across all these countries, which presumably have different chicken rearing practices. The lack of correlation between egg consumption and heart disease in all these countries leads me to believe that early researchers truly were wrong when they proclaimed eggs are “bad for your heart.”

      Slowly researchers and medical practitioners are beginning to realize fats are not all the same. The low-fat diet that has been recommended by the USDA for decades obviously is not working, as obesity and chronic disease continues to increase. It’s good to see researchers exploring other diets, like the Mediterranean diet study that was released last week.

  2. Pingback: Processed Meat Associated with Increased All-Cause Mortality | Understand Nutrition

  3. Forty-three years ago, I relied on the writings of Adelle Davis for nutritional guidance through my first pregnancy and for nourishing my baby daughter. She wrote at that time of what she considered the thoroughly bad rap suffered by the egg, based on assumptions unsupported by science. It is heartening to know that science now supports her 1970 prescience and wisdom,

    When my pediatrician wanted me to start my breastfed daughter on rice pablum at 6 weeks, I wrote Ms. Davis for advice. I will always treasure her response which encouraged me to delay the introduction of solids until 6 months.

    That baby girl? She is now the mother of two daughter’s herself, an advocate for children’s health and a blogger as well (, a link from which led me to you site.

    Many thanks

  4. Pingback: Eggs Under Fire: Review of the Another TMAO Study | Understand Nutrition

  5. Hi Bill,

    Do you know if any of these egg studies looked at the type of food being used to replace eggs in the diet? This might alter whether or not eggs are shown to exert a harmful effect.

    I ask because I have read a paper recently which made this point –

    The role of reducing intakes of saturated fat in the prevention of cardiovascular disease: where does the evidence stand in 2010?

    “When specific foods are examined, are they being compared with appropriate alternatives? For example, it may not be useful, as is usually done, to compare a specific food to all other sources of energy, which are usually mainly refined starches, sugars, red meat, and fat-rich dairy products in typical Western diets.”

    • Hi Will,

      It’s a good point that the food eggs are replaced with in the diet is important. To my knowledge, no studies have looked at replacing eggs with another specific food. Most studies just compare people that eat lots of eggs to those who do not. With that being said, these eggs studies have been performed in several countries, and eggs are presumably displaced by a variety of other foods. The vast majority of the studies find no negative cardiovascular impact when more eggs are consumed.

      Thanks for reading!

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