Eggs Improve Cholesterol
My breakfast this morning was two strips of bacon, two eggs, and coffee. This is pretty much the American standard, except that I left out the usual toast, jelly, and hash browns that would have given me more carbohydrates than I wanted. Of course, I added a little salt and hot sauce to my eggs as well as some fresh herbs and a lot of chia seeds.
But this morning for the first time I ate this breakfast without guilt.
It wasn't the saturated fat in the bacon that had made me feel guilty. For me, Gary Taubes in his new book Good Calories, Bad Calories had destroyed the myth that fat is bad for our hearts, the major complication of diabetes.
It wasn't the coffee or the caffeine in it that had made me feel guilty. I know that even though a couple of cups of coffee raises our blood glucose level a bit, drinking it also seems to give us a lot of health benefits.
It's all that cholesterol in the eggs that had made me feel guilty. Except for animal organ meats -- like the brains of beef, pork, lamb, and veal -- of all the foods we eat, eggs are the highest in cholesterol.
One large egg has about 213 milligrams of cholesterol — all of which is in the yolk. "If you are healthy, it's recommended that you limit your dietary cholesterol intake to less than 300 mg a day," according to the Mayo Clinic. But, "If you have cardiovascular disease, diabetes, or high LDL (or "bad") cholesterol, you should limit your dietary cholesterol intake to less than 200 mg a day."
The American Heart Association provides essentially the same advice. This is the conventional wisdom that made me feel guilty whenever I sat down to enjoy my bacon and eggs for breakfast.
But why the concern about dietary cholesterol? As long ago as 1937 in the Annals of Epidemiology two Columbia University biochemists, David Rittenberg and Rudolph Schoenheimer, "demonstrated that the cholesterol we eat has very little effect on the amount of cholesterol in our blood," according to research that Taubes cites in Good Calories, Bad Calories. And then, "When [Dr. Ancel] Keys fed men for months at a time on diets either high or low in cholesterol, it made no difference to their cholesterol levels."
And now new research goes even further. This new study, "Eggs Modulate the Inflammatory Response to Carbohydrate Restricted Diets in Overweight Men" by Joseph C. Ratliff and three associates at the University of Connecticut, show that eggs are actually anti-inflammatory. The full-text of the report in the journal Nutrition & Metabolism is online.
This placebo-controlled study tracked 28 overweight men who followed a low-carb diet. For 12 weeks 15 of them ate three eggs per day and 12 ate a substitute. The anti-inflammatory effect of the egg-rich diet was "possibly due to the presence of cholesterol" (emphasis added). This diet increased their level of HDL -- the "good" -- cholesterol and the antioxidant lutein, a potent antioxidant found in egg yolks.
Thanks to my correspondent, Hana, in England for bringing this fascinating article to my attention. Because eggs can actually improve our level of good cholesterol when the conventional wisdom still damns them, I find the conclusions of this new research to be counter-intuitive -- and therefore especially interesting.
Furthermore, eggs are good at helping us to feel full. They are 50 percent more satisfying than white bread, according to the satiety index. Likewise, a 2005 study in the Journal of the American College of Nutrition, "Short-Term Effect of Eggs on Satiety in Overweight and Obese Subjects," showed that 30 women ate about 686 calories less for lunch after eating either about 760 calories from eggs or the same amount from bagels for breakfast. Even 36 hours after breakfast, the egg eaters consumed fewer calories than the bagel eaters.
Even though this new research on the cholesterol in eggs has set my mind at ease when I eat my eggs for breakfast, I still had some concern about advanced glycoxidation (also called glycation) end products. This bad stuff comes from interactions between glucose and protein or between lipids (fats) and proteins. Whether you call it glycoxidation, glycation or lipoxidation, the accepted abbreviation is appropriately AGEs.
Two fried eggs have an AGEs level of about 2,700. By comparison, two boiled skinless chicken pieces have about a somewhat lower level, about 2,100. This is according to calculations based on tables in "Advanced Glycoxidation End Products in Commonly Consumed Foods." The abstract of that research in the Journal of the American Dietetic Association is online.
I was surprised that the level of AGEs in the two strips of bacon -- about 1,400 -- was considerably less than in the two eggs. And that is considerably less than the AGEs in a handful (about 25) of roasted almonds, almost 2,000.
Dr. Helen Vlassara’s research found that foods cooked at high temperatures dramatically increased the production of AGEs and that they produce inflammation-causing proteins. On the basis of my CDE's advice and Dr. Vlassara's research I now cook both my bacon and eggs at a temperature just above a simmer.
While I hope that this helps to keep the AGEs level of the foods that I enjoy down, I'm not really sure. That's because Dr. Vlassara told me that there is "no major benefit" in cooking for a longer time at a lower temperature. I just hope there is a minor benefit, because I really want to enjoy my bacon and eggs while aging well -- without too many AGEs.