American Egg Board Refutes Atherosclerosis Study

PARK RIDGE, Ill.The American Egg Board is refuting a study published in the journal Atherosclerosis that concluded regular consumption of egg yolks is about two-thirds as bad as smoking when it comes to increased build-up of carotid plaque, a risk factor for stroke and heart attack.

Researchers at Western University in Canada analyzed data from 1,231 men and women in their early 60s who were patients attending vascular prevention clinics at London Health Sciences Centres University Hospital. Ultrasound was used to establish a measurement of total plaque area and questionnaires were filled out regarding their lifestyle and medications including pack-years of smoking (number of packs per day of cigarettes times the number of years), and the number of egg yolks consumed per week times the number of years consumed (egg yolk-years).

The researchers found carotid plaque area increased linearly with age after age 40, but increased exponentially with pack-years of smoking and egg yolk-years. The study also found those eating three or more yolks a week had significantly more plaque area than those who ate two or fewer yolks per week.

The American Egg Board said the findings are surprising and contradict more than 40 years of research demonstrating that healthy adults can enjoy eggs without significantly impacting their risk of heart disease.

Eggs have been shown to have a wide range of health benefits, providing 13 essential vitamins and minerals, high-quality protein and antioxidants, all for just 70 calories. Years of credible research has demonstrated the positive effects of the high-quality protein and nutrients in eggs on satiety, weight management, eye health and in supporting a healthy pregnancy.

The 2010 Dietary Guidelines for Americans recognize eggs as a nutrient-dense food that can be part of a healthful diet," said Mitch Kanter, PhD, Executive Director of the Egg Nutrition Center. While eggs provide many nutrients and make an important contribution to overall diet quality, they are often accompanied by foods high in saturated fat and calories. These pairings were not taken into consideration in the Atherosclerosis study."

The American Egg Board also noted the Atherosclerosis study is an observational study that can only suggest potential relationships, not determine actual cause-and-effect conclusions. In this study, it is important to note that the researchers did not account for any dietary or behavioral factors beyond egg intake and smoking. The study did not control for exercise habits, waist circumference, intake of saturated fat, alcohol or foods commonly eaten with eggs like high-fat meats and other high-fat side dishes.

Study subjects with higher egg intakes tended to also be heavy smokers, and only a small percentage of the population consumed more than five eggs per week, meaning that the conclusions were based on a small number of subjects. Lastly, although the study shows a link between egg consumption and carotid plaque area, no associations to many traditional markers of cardiovascular disease, including total serum cholesterol, LDL-cholesterol, HDL-cholesterol or body mass index (BMI) were reported.

The American Egg Board pointed to a Harvard study with more than 100,000 subjects that found no significant difference in cardiovascular disease risk between those consuming less than one egg per week and those consuming one egg per day. The researchers concluded that consumption of up to one egg per day is unlikely to have substantial overall impact on the risk of heart disease or stroke among healthy men and women.

Another study published in Risk Analysis estimates that eating one egg per day is responsible for less than one percent of the risk of coronary heart disease in healthy adults. Alternatively, lifestyle factors including poor diet, smoking, obesity and physical inactivity contribute to 30% to 40% of heart disease risk, depending on gender. Additionally, research has shown that saturated fat may be more likely to raise a persons serum cholesterol than dietary cholesterol.