Sunday, March 6, 2022

Eggs - Superfood


 


Recently, I've been surprised to learn new facts about nutrition.  This is curious to me, because not many people have kept their ears to the ground the way that I have on diet factoids.  


What surprising factoids have suddenly come to my attention?  The fact that the quality of protein from animal and plant sources can be vastly different.   Is meat, poultry, and fish a good source of protein?  Yes and no.  Problem.  Thirty grams of meat protein eaten doesn't equal thirty gram of protein going to the body in the form of protein.  What??!!  When did I start to notice this?  I started checking my blood glucose before and an hour after eating steak.   My glucose would inevitably be higher after I ate beef!  But why? 


I am on the ketogenic diet, and I have been for probably half my life now, because mainly, it helps with all sorts of issues.  But after a while I never seemed to be in ketosis and I never lost weight.  So I went carnivore for a while to see if that worked better.  That's when I noticed that even the complete lack of carbs in my diet did not result in ketosis.  In fact, eating no carbs at all for days not only didn't result in ketosis, but I could eat a steak and see my blood glucose go up!  That didn't make sense.  


Oh, it makes sense.  The reason is that the amino acid profile of meat, like beef, is such that only 32% of the protein will be digested by the body.  The rest of the steak is converted by the body into energy, by the process of gluconeogenesis.  The body then either uses the new glucose source for immediate purposes, like running a few miles, or stores it in the form of fat for a rainy day.  A rainy day that never seems to come.  This is not a lot different from what the body does with a candy bar.   This is also true for pork, fish, and poultry.  Does my body hate me?  I'm not sure.  We're not as good a friends as I thought we were.  


Oh, but what about milk, and dairy, so often called "the perfect food?"  Well, if the protein profile of the perfect food is such that 17% of the protein arrives safely into the digestive system to nourish and rebuild tissues such as muscle and vital organs, then perfection has been achieved.  And then the rest goes into energy and frequently is converted to fat, again, just like a candy bar.  Then why do so many articles call it the perfect food?  Article after article puts forth the notion that egg protein is "almost as good as milk." 


Let me state unequivocally that milk protein is much less bioavailable to the human body than egg protein.   Oh, what is the definition of milk?  Well, I suppose one could pretend that we are speaking of human breast milk, and in that case, yes, the bioavailability is slightly better than the egg.  We're not talking about human breast milk unless you are less than five years old.  We're usually talking about cow milk.  It is in no way as good for humans as human breast milk.  Even human breast milk loses some of its luster once one is no longer a toddler, because,  as often as not, people will lose the bulk of the enzymes necessary to digest lactose.  


So I'm not sure where the bestowing of sainthood upon milk came from.  That idea is just not correct.  It's not how it is.  The protein profile of cow's milk, and even goat's milk, is just not ideal for people. 


What do I mean by "protein profile?"  Well, what are the essential amino acids?  Leucine, valine, isoleucine, lysine, phenylalanine,  threonine,  methionine,  and tryptophan.  From these essential amino acids the body can make all the other amino acids it needs, and from those, make the amino acids into protein.  But in order for this to happen, the essential amino acids must be in the proper propotions.  Suppose you needed 10 grams of each amino acid to make protein, but wait, you only had one gram of isoleucine in your food of choice but 10 grams of all the other amino acids?  Would the body go ahead and make 10 grams of protein anyway?  No way!  It would make one gram of protein, since it needed all eight essential amino acids, and it only had one gram of all eight.  So the rest goes to energy, and frequently, fat.  


Correction.  There are nine essential amino acids.  I left out histidine.  I had a conversation about this with the PerfectAmino people and they say that histidine is a conditional amino acid, meaning that if one has the other eight in ideal quantities, the body will raise histidine levels.  Therefore histidine is not an essential amino acid.  Is this correct?  I would say it's debatable.  


So, of all the protein sources in the diet, the star is the egg, since it contains the most perfect proportions of amino acids for the needs of the human body, the protein being 48% bioavailable.  The protein of milk is only 17% bioavailable, thus it is no where near the quality of egg protein.  I suppose the thinking was that since cow milk totally nourishes calves early in their lives, that makes it the ideal food for us.  Well, it just ain't so.  In fact, the quality of all sources of protein in the diet are rated on a scale with the egg being the best, and other proteins being graded on quality compared to the top quality of the egg.  


Oh, then there is one other egg error that has surprised me to see being put forth.  There are those out there in internet land saying that the egg white contains 100% of the protein of the egg, and the yolk contains no protein.  The fact is, the yolk, by volume, contains more protein than the white.  However, the yolk comprises less of a whole egg than the white.  


So, if possible, eat your eggs.  





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