Eggs and Cardiovascular Health: A Continuing Controversy
The role of eggs in the incidence of cardiovascular disease has been examined for decades. In 2016, a meta-analysis of prospective cohort studies concluded that, overall, there was no clear association between egg intake and increased or decreased risk of CHD. (1) However, a meta-analysis published in 2019 found that, among U.S. adults, a higher intake of eggs was associated with higher incident risk of cardiovascular disease. (2)
The strengths of the meta-analysis were the use of:
- a large U. S. cohort observational studies (ARIC, CARDIA, FHS, FOS, JHS, and MESA),
- a diverse sample that was 31.1% Black,
- a standardized technique to equalize various dietary assessments across studies
- cohort-stratified standard proportional hazard modeling, controlling for many demographic and clinical variables.
The authors also provide limitations of the meta-analysis:
- measurement error for self-reported dietary data
- single measurement of egg consumption
- data not available to analyze subgroups such as stroke.
Questions remain about whether the finding can be generalized, for example to the UK where egg consumption is half that of the U.S. (3), and whether there might be a problem with underreporting egg intake (4).
Given that a moderate effect was obtained in this most recent meta-analysis from studies that are fairly strong in their data quality, cardiovascular nurses should remind patients that eggs should be eaten in moderation. Eggs are a nutrient-dense and low-cost food that provides essential fatty acids, protein, antioxidants, and important vitamins and minerals (1). Yet eggs are also a source of saturated fat. Regarding prevention, the replacement of saturated fat with dietary mono and polyunsaturated fats whenever possible reduces cardiovascular risk. (5)
- Alexander, D. D, Miller P. E., Vargas, A. J., Weed, D. L., & Cohen, S. S. (2016). Meta-analysis of egg consumption and risk of coronary heart disease and stroke. Journal of the American College of Nutrition, 35, 704-716.
- Zhong, V. W. et al. (2019). Associations of dietary cholesterol or egg consumption with incident cardiovascular disease and mortality. JAMA, 32, 1081-1095.
- Mayor, S. (2019). Research news: Higher intake of cholesterol or eggs linked to increased risk of cardiovascular disease and death, finds study. BMJ, 364, l1214. doi: 10.1136/bmj.l1214
- Keyserling, T., C., Berkowitz, S. A., & Samuel-Hodge, C. D. (2019). Letter to the Editor: Dietary cholesterol and egg consumption and cardiovascular outcomes. JAMA, 32(5), 466-467.
- Arnett, D., Blumenthal, R. A., & …Wijeysundera, D. (2019). 2019 ACC/AHA guidelines on the primary prevention of cardiovascular disease. Journal of the American College of Cardiology. Retrieved from https://doi.org/10.1016/j.jacc.2019.03.010