Wednesday, August 15, 2012

Should We Eat the Chicken or the Egg?

My healthy 90 year old mom.

It seems like every week or so there is a new study on another thing that is  harmful to our health or well being. Unfortunately, many times the culprit is something in our diet or environment that we are attached to, or have always considered safe. The new study on the danger of eating egg yolks is certainly one of these. 
The headline is shocking, since the new study compares eating egg yolks with smoking cigarettes. What??  Of course, it is not news that egg yolk is high in cholesterol. To quote a section of an article by Melissa Healy at the Los Angeles Times: 
"The study subjects were typically referred to the clinic after having suffered a clot-induced stroke or a transient ischemic attack -- a "mini-stroke" in which symptoms may disappear quickly but which often presage a more serious stroke to come."
"Smoking tobacco and eating egg yolks increased carotid wall thickness in similar fashion -- which is to say, the rate of increase accelerated with each stair-step up in cigarette smoking or yolk consumption. By contrast, for those who did not smoke, or who rarely consumed egg yolks, carotid wall thickness increased after 40, but at a slow-steady rate. " 
Now, hopefully the study printed in the journal Atherosclerosis, was conducted according to standard research methods, meaning that subjects were screened for factors that could confound the results. That is, if the subjects had already experienced cardiovascular incidents, as indicated, what factors in their lifestyle besides eating egg yolk might have contributed?
In my opinion, it is even more important to ask whether any information is known about the subjects' genetic predisposition to heart disease. To use a personal example, which is in no way unique, my 90 year old mother has all her life, eaten a diet high in cholesterol. Her main staples are eggs, bacon, and red meat.  Her doctor says she is one of his healthiest patients over the age of 60. That is because she has low LDL cholesterol and no signs of diabetes or heart disease.  She has never exercised outside her normal daily activity. 
On the other hand, I had breast cancer and have no discernible risk factors. I have always exercised, eaten a healthy diet, and do not smoke. I suspect this is a genetic tendency similar to my mother's tendency to avoid heart disease no matter what she eats.
So, what should we make of this latest study? The protein in eggs is healthy; it is the fat that is the problem.  One issue here is that there are eggs and egg products in a myriad of baked goods and other processed foods and those must be factored into the assessment of how much egg yolk we actually eat. 
Like my mom, I am fortunate to have naturally very low LDL and high HDL (good cholesterol). However, given a choice between the chicken and the egg, I will choose to eat chicken. I will not cut the occasional omelet out of my diet, but I will probably further reduce the number of eggs--yolk, since the white does not contain cholesterol--I eat over all.
The bottom line is as we have said many times, we should make dietary decisions based on knowledge of our cholesterol and blood sugar numbers, as well as well established guidelines on the amount of sugar and animal fat we should consume, which is very little.  Here is the link to the article. http://www.latimes.com/health/boostershots/la-heb-egg-cholesterol-smoking-20120814,0,1391259.story