Cholesterol in Eggs and Heart Health

If you love eggs but have shunned them because of concerns about dietary cholesterol, it’s time to reassess and get cracking.

A 2016 study from the University of Eastern Finland shows that a relatively high intake of dietary cholesterol, or eating one egg every day, is not associated with an elevated risk of incident coronary artery disease (CAD). What’s more, the study findings, published in the American Journal of Clinical Nutrition (2016; 103 [3], 895–901), reported no association for subjects with the APOE4 phenotype, which negatively impacts cholesterol metabolism.

In the majority of the population, dietary cholesterol affects serum cholesterol levels only a little, and few studies have linked the intake of dietary cholesterol to an elevated risk of cardiovascular diseases. Globally, many nutrition recommendations no longer set limitations on the intake of dietary cholesterol. However, in carriers of the apolipoprotein E type 4 allele—which significantly impacts cholesterol metabolism—the effect of dietary cholesterol on serum cholesterol levels is greater. In Finland, the prevalence of the APOE4 allele, which is hereditary, is exceptionally high and approximately one-third of the population are carriers.

The dietary habits of 1,032 men aged 42–60 with no baseline diagnosis of any cardiovascular disease were assessed at the onset the Kuopio Ischaemic Heart Disease Risk Factor Study in 1984–1989 at the University of Eastern Finland. During a follow-up period of nearly 21 years, 230 men had a myocardial infarction; 32.5% of the study participants were carriers of APOE4.

The study found that a high intake of dietary cholesterol was not associated with increased risk of CAD—not in the entire study population nor in those with the APOE4 phenotype. Moreover, consumption of eggs, a significant source of dietary cholesterol, was not associated with increased risk of CAD. The study did not establish a link between dietary cholesterol or eating eggs with thickening of the common carotid artery walls, either.

The findings suggest that a high-cholesterol diet or frequent consumption of eggs does not increase the risk of CAD even in those who are genetically predisposed to a greater effect of dietary cholesterol on serum cholesterol levels. In the highest control group, study participants had an average daily dietary cholesterol intake of 520 milligrams and consumed an average of one egg per day, which means the results cannot be generalized beyond these levels.