Eggs are rarely found in ‘unhealthy food’ lists, but a new study suggests that their regular consumption is not as beneficial to our health in the long run. A strong link has been found between the consumption of 3 or more egg yolks a week and atherosclerosis—the thickening of the blood vessels which is associated with cardiac disease and stroke.
Eggs are Cholesterol-rich
The yolk of eggs contains a little less than the total protein in the egg, and virtually all its fat and vitamins. A single egg yolk contains more than two-thirds the daily recommended amount of cholesterol. However, despite widespread measures to reduce cholesterol intake, eggs have not come under the scanner, because there has been no consensus on their effects on serum cholesterol. There has been prior research saying that eating up to one egg a day does not have any effect on heart disease, though eating even moderate quantities of eggs (6 a week) can increase chances of cardiovascular disease in diabetic patients.
Fatty Deposits on Blood Vessels
Researchers at the University of Western Ontario studied Canadian participants who had been admitted to vascular prevention clinics and measured the area of the carotid plaque—the layer of fats and cholesterol deposits—using ultrasound. The higher the plaque area, the more blocked your blood vessels get. It’s akin to a cylindrical pipe with moss on its walls, slowly blocking water flow as the moss grows larger. They had data on long-term egg-consumption and smoking for 1231 patients. While no link was seen between cholesterol levels and egg yolk consumption, they did find that the carotid plaque area increased with increasing levels of yolk consumption.
The increase in carotid plaque area increases exponentially with both smoking and egg yolk consumption, as opposed to just linearly with age. “What we have shown is that with aging, plaque builds up gradually in the arteries of Canadians, and egg yolks make it build up faster – about two-thirds as much as smoking.” said Dr. David Spence, who headed this study.
Further study has to be conducted taking into account factors like exercise and waist size which could also be significant factors that could affect the results. For instance, if a majority of the 1231 participants fell into the low-exercise category, then perhaps egg yolk consumption is harmful only in the absence of exercise. Moreover, this research was only conducted on people who already suffered from cardiovascular disease. We do not know if the same effects will be seen in a similar cohort of unaffected individuals. Cardiovascular disease is caused by a host of factors, and it is difficult to say how much of an effect one factor, like egg yolk, alone can have. Until more conclusive evidence is found, however, you might want to think about r-egg-ulating the amount of eggs in your diet.
You can read about this research here.