Eggs Do Not Increase Heart Attack Risk, Finnish Study Finds

Jyrki Virtanen, PhD, adjunct professor of nutritional epidemiology at the University of Eastern Finland, and lead author of the study, told NutritionInsight: “Cholesterol-restricted diets are also lower in saturated fat (because cholesterol and saturated fat often exist in the same sources), which has a much greater impact on serum cholesterol levels than dietary cholesterol intake. Therefore, the message of our study is not that one could freely put back cholesterol-rich foods like bacon and butter, which would then also increase the saturated fat intake.”

In the majority of 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 to the intake of dietary cholesterol. However, in carriers of the APOE4, the effect of dietary cholesterol on serum cholesterol levels is greater. In Finland, the prevalence of the APOE4 allele, which is a hereditary variant, is exceptionally high and approximately one third of the population are carriers. Research data on the association between a high intake of dietary cholesterol and the risk of cardiovascular diseases in this population group hasn't been available until now.

 

The findings were published in the American Journal of Clinical Nutrition. No association was found among those with the apolipoprotein E type 4 (APOE4) allele phenotype, which affects cholesterol metabolism and is common among the Finnish population.

 

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

 

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

 

In the highest control group, the study participants had an average daily dietary cholesterol intake of 520 mg and they consumed an average of one egg per day, which means that the findings cannot be generalised beyond these levels.

 

“What our study indicates is that dietary cholesterol itself is not associated with a higher risk of CHD and neither is higher intake of eggs, which is a major source of dietary cholesterol, but not a major source of saturated fat,” Virtanen concluded.