The 2015 Dietary Guidelines Advisory Committee (DGAC) made both history and headlines when dietary cholesterol was removed from the list of nutrients of public health concern.1 Up until this point, there had historically been a limit of 300 milligrams per day for dietary cholesterol, even though eggs were listed as a nutrient-rich food and part of healthy dietary patterns in previous guidelines.2
In making the decision to not bring a cholesterol limit forward for recommendations, the 2015 DGA committee referenced, among other sources, a 2013 systematic review that examined the relationship between egg consumption and cardiovascular disease in almost 350,000 participants across 16 studies.3 The review and meta-analysis found no relationship between egg intake and cardiovascular disease, ischemic heart disease, or stroke.
Since 2015, the science evaluating the relationship between dietary cholesterol, eggs, and cardiovascular health has continued to grow. One observational study of U.S. cohorts published early in 2019 found a small but statistically significant increase in cardiovascular risk with egg consumption. 4 However, another observational study analyzing data from over 400,000 men and women in Europe for over an average of 12 years, found a small but statistically significant decrease in risk for ischemic heart disease with egg intake.5
It is important to note that observational studies examining eggs are likely confounded by other dietary components, thus it is important to also examine results from randomized controlled trials.6 These trials consistently show only modest effects, if any, of egg intake on cardiovascular risk factors.6 In some cases, eggs show a significant benefit, as was the case with another 2019 study that reported improved function of high-density lipoproteins (HDL) after an intervention that included approximately 2 whole eggs per day.7
In 2019 two global health organizations re-assessed the science since the 2015 DGA and provided new recommendations around dietary cholesterol, eggs, and heart-healthy diet patterns that both build on previous findings and provide some helpful details.
First, the Australian Heart Foundation (AHF) made international headlines in 2019 with a new position statement on eggs and cardiovascular health.8 The AHF summary concluded there is no evidence to suggest any limit on egg consumption for normal, healthy individuals. The review does suggest a limit to fewer than 7 eggs per week for those with type 2 diabetes or cardiovascular disease that require LDL cholesterol-lowering interventions. However, these AHF guidelines were clearly a step forward in acknowledging the scientific evidence that shows eggs can be part of a heart-healthy eating pattern when consumed with fruits, vegetables, whole grains, nuts, legumes, and other lean proteins.
Additionally, in late 2019, the American Heart Association (AHA) Nutrition Committee published a science advisory on Dietary Cholesterol and Cardiovascular Risk.6 According to the authors, “the elimination of specific dietary cholesterol target recommendations in recent guidelines has raised questions about its role with respect to cardiovascular disease.” This review examined evidence from observational cohorts and randomized controlled trials and concluded that “a recommendation that gives a specific dietary cholesterol target within the context of food-based advice is challenging for clinicians and consumers to implement; hence, guidance focused on dietary patterns is more likely to improve diet quality and to promote cardiovascular health.” The science advisory recommends that within the context of heart-healthy eating patterns, such as the Mediterranean-style and DASH (Dietary Approaches to Stop Hypertension)–style diets, replacing saturated fats is expected to produce greater reductions in LDL cholesterol concentrations than reducing dietary cholesterol alone. Specifically, the advisory concluded:
- To achieve healthy dietary patterns, consumers are advised to eat a dietary pattern characterized by fruits, vegetables, whole grains, low-fat or fat-free dairy products, lean protein sources, nuts, seeds, and vegetable oils, consistent with those recommended in the 2015 to 2020 DGA.
- Healthy individuals can include up to a whole egg daily in heart-healthy dietary patterns.
- For older healthy individuals, given the nutritional benefits and convenience of eggs, consumption of up to 2 eggs per day is acceptable within the context of a heart-healthy dietary pattern.
- Vegetarians who do not consume meat-based cholesterol-containing foods may include more eggs in their diets within the context of moderation.
The release of these new guidelines in 2019 from leading health organizations demonstrates how the science on dietary cholesterol and eggs continues to reinforce the 2015 DGAC report’s recommendation to not limit dietary cholesterol to an arbitrary number. Eggs can be a part of a heart-healthy eating pattern. In fact, vegetarians (lacto-ovo) and older individuals have reason to incorporate even more eggs into their diets, according to the AHA. Indeed, eggs are more than just a source of dietary cholesterol. Eggs provide a good or excellent source of eight essential nutrients including choline, six grams of high-quality protein, 252 mcg of the carotenoids, lutein and zeaxanthin, making them the perfect complement to heart-healthy diets.
References
- Dietary Guidelines Advisory Committee. Scientific Report of the 2015 Dietary Guidelines Advisory Committee: Advisory Report to the Secretary of Health and Human Services and the Secretary of Agriculture,. 2015
- Dietary Guidelines Advisory Committee. Scientific Report of the 2010 Dietary Guidelines Advisory Committee: Advisory Report to the Secretary of Health and Human Services and the Secretary of Agriculture,. 2010
- Shin, J.Y., et al., Egg consumption in relation to risk of cardiovascular disease and diabetes: a systematic review and meta-analysis. Am J Clin Nutr, 2013. 98(1): p. 146-59.
- Zhong, V.W., et al., Associations of Dietary Cholesterol or Egg Consumption with Incident Cardiovascular Disease and Mortality. JAMA, 2019. 321(11): p. 1081-1095.
- Key, T.J., et al., Consumption of Meat, Fish, Dairy Products, Eggs and Risk of Ischemic Heart Disease: A Prospective Study of 7198 Incident Cases Among 409,885 Participants in the Pan-European EPIC Cohort. Circulation, 2019. 18;139(25):2835-2845.
- Carson JAS, Lichtenstein AH, Anderson CAM, Appel LJ, Kris-Etherton PM, Meyer KA, Petersen K, Polonsky T, Van Horn L; on behalf of the American Heart Association Nutrition Committee of the Council on Lifestyle and Cardiometabolic Health; Council on Arteriosclerosis, Thrombosis and Vascular Biology; Council on Cardiovascular and Stroke Nursing; Council on Clinical Cardiology; Council on Peripheral Vascular Disease; and Stroke Council. Dietary cholesterol and cardiovascular risk: a science advisory from the American Heart Association. Circulation. 2019;140: e-pub ahead of print.
- Sawrey-Kubicek, L., et al., Whole egg consumption compared with yolk-free egg increases the cholesterol efflux capacity of high-density lipoproteins in overweight, postmenopausal women. Am J Clin Nutr, 2019. 110(3):617-627.
- Australian Heart Foundation; Eggs and Cardiovascular Health: Summary of Evidence. 2019.