HAMILTON, ONT. — Eating on average one egg a day or less was not associated with increasing the risk of heart disease, according to an analysis of three long-term multinational studies. Researchers from the Population Health Research Institute of McMaster University in Hamilton and Hamilton Health Sciences performed the analysis, which appeared online Jan. 21 in The American Journal of Clinical Nutrition and may be found here.

“Moderate egg intake, which is about one egg per day in most people, does not increase the risk of cardiovascular disease or mortality even if people have a history of cardiovascular disease or diabetes,” said Mahshid Dehghan, Ph.D., an investigator at the Population Health Research Institute. “Also, no association was found between egg intake and blood cholesterol, its components or other risk factors. These results are robust and widely applicable to both healthy individuals and those with vascular disease.”

The three studies combined involved about 177,000 people of different income levels from 50 countries spanning six continents.  A Prospective Urban Rural Epidemiology (PURE) study involved 146,011 people from 21 countries. Higher egg intake, seven eggs or fewer per week compared to less than one egg per week, was not significantly associated with blood lipids, total mortality or major cardiovascular disease.

Another 31,544 patients with vascular disease were analyzed from two multinational prospective studies: ONTARGET (Ongoing Telmisartan Alone and in Combination with Ramipril Global End Point Trial) and TRANSCEND (Telmisartan Randomized Assessment Study in ACEI Intolerant Subjects with Cardiovascular Disease). Similar results to the PURE study were found for total mortality and major cardiovascular disease.

The Population Health Research Institute, the Canadian Institutes of Health Research, the Heart and Stroke Foundation of Ontario, and the European Research Council provided funding for the analysis, as did grants from several pharmaceutical companies and from health agencies or ministries of 18 countries.

The researchers pointed out eggs are a nutrient-dense, rich source of protein and bioactive compounds such as lutein and zeaxanthin, but some cardiovascular guidelines recommend limiting egg consumption since they adversely may affect blood lipids due to their high cholesterol.

“In recent years, however, randomized trials, animal studies and mechanistic studies have shown that dietary cholesterol has little effect on blood lipids,” the researchers wrote.

The Dietary Guidelines for Americans 2010 recommended people consume less than 300 mg per day of cholesterol, but the 2015-2020 Dietary Guidelines for Americans did not include that recommendation. The 2015-2020 version recommended people eat a variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products. The U.S. Department of Agriculture and the U.S. Department of Health and Human Services should release an updated version of the Dietary Guidelines for Americans later this year.