Eating egg yolks on a regular basis increases plaque buildup nearly two-thirds as much as smoking does, according to a new study published online in the journal Atherosclerosis.
Researchers looked at 1,231 patients with an average age of 61.5. Each of these patients at the vascular prevention clinics at London Health Sciences Centre's University Hospital had already experienced high blood pressure, hypertension, a small stroke or a family history of cardiovascular disease.
After filling out questionnaires about lifestyle, diet and medications, how much they smoked and the number of egg yolks they ate, patients underwent an ultrasound scan to examine their plaque buildup. The study did not account for waist circumference or exercise program.
Patients who ate three or more yolks a week showed significantly more plaque than those who ate two or fewer yolks per week.
Dr. Gordon Tomaselli, chief of cardiology at John Hopkins University School of Medicine and the former president of the American Heart Association, said the research confirms what doctors already know about eating cholesterol and cardiovascular disease.
"Cholesterol intake should be limited to 300 milligrams a day, particularly in people who do not have underlying heart disease," he said.
Lead study author Dr. David Spence, a professor of neurology at the University of Western Ontario's Schulich School of Medicine & Dentistry, adds, “The issue is with the yolk, not the egg. One jumbo chicken egg yolk has about 237 milligrams of cholesterol.”
He also says that keeping a diet low in cholesterol is key, noting that even if you are young and healthy, eating egg yolks can increase the risk of cardiovascular diseases later on in life.
In this study, patients with a higher likelihood of cardiovascular issues were used in order to get more visible results instead of using the general population with a lower risk.
CNN Wires contributed to this report.