Now that we know the reasoning, and I use that term loosely, behind why low cholesterol, low fat diets started, let us examine in a little more detail the substance called cholesterol. We will look at fats a little bit later.
Cholesterol is considered a type of fat, a sterol to be precise. Its production starts with sugar molecules. Please read the preceding sentence a thousand times again and again. Yes, cholesterol production begins when the cells of the body see sugar molecules. These sugar molecules can be glucose (found in starches, processed and unprocessed foods and all vegetables), fructose (found in fruit and berries) and galactose (found in lactose which is comprised of glucose and galactose). These sugar molecules will be modified within the cells of the body with the end result being the production of cholesterol.
One may ask, "Why would our bodies make such a deadly substance?"
Our bodies make cholesterol because our cells, each and every one of them, need cholesterol to survive. Cholesterol is found in our cell’s membrane, is the starting point for the production of hormones like testosterone, estradiol, progesterone, cortisol and bile acid salts and the list goes on. Without cholesterol in our cell’s membrane and without the other things we make from cholesterol; we will die. The cell membrane is what makes a cell, a cell. Without a cell membrane we have no cells and there is no us. Without the other stuff we make from cholesterol we could not survive either.
Getting back to how cholesterol is made I know what you are thinking; "How come I was never told that cholesterol is made from sugar?" How come you were never told that the very foods that DO NOT contain cholesterol or fat are the very foods that the body uses to make cholesterol and fat. It is because doctors, dieticians and nutritionists have forgotten themselves.
For my physician readers, remember glycolysis? Come on, I bet you do. Remember the end product of glycolysis that thing called pyruvate. Does acetyl Co A ring a bell? It should. It comes from the modification of pyruvate during the aerobic metabolism of glucose. Now who out there remembers that when two molecules of acetyl Co A come together it forms acetoacetyl Co A? Huh? Any takers?
OK, this is for extra credit. Does anyone remember that "all twenty seven carbon atoms found in cholesterol come from acetyl CoA? (1) Mevalonate ring a bell. How about squalene? OK, OK I will stop now. It was embarrassing for me too when I came to the realization that I had forgotten how cholesterol was made. Even more so for me because I was a nutritional biochemist trained at one of the most prestigious universities in the world. And I even had forgotten this simple, basic biochemical fact.
But please do not go on thinking that the cholesterol made in the body comes from anything other than the modification of a sugar molecule. This is so utterly important to understand and so crucial it bears repeating. Cholesterol is made in the body from sugar. It is through the modification of a sugar molecule that we make the majority of cholesterol in our bodies. And this is the cholesterol that clogs up all our arteries, including our coronary arteries, leading to subsequent heart attacks.
Now to get to cholesterol from sugar molecules requires a review of biochemical pathways, physiological feedback loops (say that three times fast) and a whole bunch of other biochemical mumbo jumbo which is enough to give anyone a headache. That is why I stopped a few paragraphs ago. But do not worry for we will be reviewing no biochemical pathways here.
Suffice it to say that sugar is the starting point for cholesterol production. So every time you eat something which contains sugar you are setting in motion the processes that the body needs to make cholesterol.
Now it must be mentioned that the cells of the body produce a greater amount of cholesterol than is consumed by us daily. (2) This means we are producing more cholesterol than we are eating. So let me ask a question; if we want to effectively lower our cholesterol and I mean effectively, would I modify my dietary intake of cholesterol or attempt to modify the body's production of cholesterol?
Well, let us think this through. The body makes more cholesterol than I consume. So if I can somehow modify how much cholesterol my body makes I will effect a greater change on my cholesterol numbers. If I change how much cholesterol I am eating, I will change the number less. But is this not exactly what we are doing when we change our dietary consumption of cholesterol by following low fat, low cholesterol diets? By following the accepted diet for reducing cholesterol you are marginally influencing the cholesterol number.
By lowering your carbohydrate intake (I like the moniker carbs for short so from now on when I am referring to carbohydrates I will just say carbs) you are lowering the amount of sugar molecules a cell sees and if the cell sees less sugar the cell makes less cholesterol. It is that simple. Really, it is.
As a side note, carbs are broken down into sugars, so whenever one eats carbs the cell will see sugar.
Now I mentioned above and the statement was taken directly from one of the most widely used Medical Physiology textbooks in colleges across America, that it is the body's own production of cholesterol that contributes most to the cholesterol present in our bodies.
So let us combine some thoughts. By lowering your carb intake the cell sees less sugar. Less sugar means less cholesterol production by our cells and now you just altered the most important contributor to cholesterol production in the body. Yes, again it is that simple. So simple it is embarrassing. But wait, it gets even more embarrassing.
Ok, so some people may be wondering what happens when we eat cholesterol. After all, doctors are taught that it is the cholesterol we eat which gets us in trouble. Are you sitting down? I hope so because here is the kicker. When we eat cholesterol our body actually diminishes its production of cholesterol. Huh? Do you mean to tell me that when I eat cholesterol my body actually slows down its production of cholesterol?
Yes, that is correct.
So let us put some more ideas together. The low cholesterol diet means more whole grains (carbs), fruits (carbs) and vegetables (carbs), and obviously less cholesterol. Guess what you just did. You just set in motion all the body needs TO MAKE MORE CHOLESTEROL! Can I hear a great big Oops!!!!
It is the classic negative biofeedback loop that makes this happen. When one ingests cholesterol since it is a fat it can transfuse right through the cell and nuclear membranes. Eventually it binds with the actual DNA of the cell and turns off the production of the enzymes that make cholesterol. Specifically, the production of the enzyme 3-hydroxy-3-methylglutaryl CoA reductase is significantly lowered. Since this is one of the most important enzymes for cholesterol formation, turning off the production of this enzyme will decrease the production of cholesterol in our bodies.
So that is why low cholesterol diets do not work to significantly lower the level of cholesterol in the blood. Going through it one more time, when we eat carbs and since the majority of cholesterol in our blood is produced by the body; we provide the cells with what they need to make more cholesterol. And then by lowering cholesterol consumption this sends the message to our body to make more cholesterol. This is because our cells, when they see less cholesterol, will make more of that enzyme mentioned above (3-hydroxy-3-methylglutaryl CoA reductase). Then more cholesterol will be made. I refer to this as the double whammy effect.
Now you physician readers may be feeling a little uneasy because I have not mentioned that lowering one's intake of cholesterol in the diet, will oftentimes lower the cholesterol number in the blood stream. Yes, this does happen, but we do not see a significant lowering of the cholesterol number. In fact, in a perfect body, and well who would that be; you only get a lowering of about fifteen percent. So if your cholesterol is, say, 300, which is not an uncommon number to see; by dramatically reducing the cholesterol in your diet, you can possibly (and usually not) lower the number from 300 to 255. For most people, this would not have lowered the cholesterol number enough, and guess what? Now your doctor is reaching for medication to help lower the cholesterol number more.
I often times will say to my patients and colleagues, who never seem to understand my reasoning, because either they do not want to, or truly just don't understand, that if the dietary contribution to your cholesterol number is only fifteen percent, what contributes the other eighty five percent? Well, it is what your body makes of course. So would it not make sense to try to modify my body's production of cholesterol, since this contributes more to the cholesterol number? Of course! This makes perfect sense, but by starting yourself on a low cholesterol diet, and by eating more carbs, and you have to eat more carbs, because that's all that's left, again, you set in motion all the things the body needs to make more cholesterol.
OK, I think I have said enough about cholesterol and we will talk more about it later. Remember, some people will question what I have written in this chapter possibly challenging what I say as untrue, but it is not. All one has to do is go to any biochemistry text and read the part on how we make cholesterol, to see that what I say is a fact.
You can take a break if you wish before we get to the next chapter where we will talk about that scary fat (which is not really all that scary) the triglyceride (said with a rising fiendish, menacing, guttural tone).
Enslavement by illusion is comfortable; it is the liberation by truth that people fear