By Michael Greger M.D.

IN REACTION to a  study that found a similar exponential increase in artery clogging plaque in both smokers and egg eaters, one critic countered that eggs have beneficial effects on, the inner lining of our arteries, citing a 2005 study on egg consumption and endothelial function, funded by: The American Egg Board.

The study was done on a group of men and women eating the standard American diet, who were overweight, had “normal” cholesterol, (which is to say extremely high cholesterol ,levels twice as high as could be considered optimal).

As the authors of a paper published in the Journal of the American College of Cardiology note, it’s often not appreciated “that the average blood cholesterol level in the United States, the so-called normal level, was actually too high,” accelerating heart disease and “putting a large fraction of the so-called normal population at a higher risk” for coronary heart disease, our number one killer.

If we threw a lit match into a flaming pool of gasoline and saw no real difference in the height of the flames, we can’t conclude that throwing lit matches into gasoline is not a fire hazard. But that is exactly what the Egg Board study concluded. When the addition of eggs didn’t make the arterial function worse than it already was, they concluded that “short-term egg consumption does not adversely affect endothelial function in healthy adults.”

The egg board paid for a follow-up study using folks who were even worse off, with a mean total cholesterol of 244. They reported that egg consumption had no effect on endothelial function… as compared to sausage and cheese. Yet instead of sounding the alarm that eating eggs is as bad for arterial function as a McDonald’s Sausage McMuffin (!), the researchers concluded that egg consumption was found to be non-detrimental to endothelial function and cholesterol levels. The subjects started out with life-threatening cholesterol, and ended up with life-threatening cholesterol.

Why don’t endothelial function and cholesterol levels get even worse? Because there’s a plateau effect. We can basically max out on our cholesterol absorption. After a certain level of intake, it’s just another match to the fire. If we’re already consuming the standard American diet averaging 400mg of cholesterol daily, even adding two jumbo eggs to our diet may not have a sizeable impact. But to people trying to eat healthy, those two eggs could shoot their cholesterol up 20 points.

However, a fat-free, cholesterol-free egg substitute was found to be beneficial. That is, not eating eggs lowers cholesterol levels and improves endothelial function—and that’s what these people needed. Their arteries were already hurting, they needed something to bring the fire down, not more matches. The subjects were apparently eating so unhealthy that adding eggs couldn’t make things much worse, but eating oatmeal instead of eggs made things better, helping to quench the fire. So even the Egg Board-funded studies said that not eating eggs is better for our arteries, yet these are the same studies that pro-egg folks cite to claim beneficial vascular effects.