It's not the fats, Silly

On a web blog there was this argument going on between an Indian member and others. The Indian was scared that if he ate way too many fats, the grease would end up in his arteries, which would then be clogged up, and he'd die of heart disease. That is how he had been scared (to death) by his doctors.

Let's ponder on that argument for a while. Does this line of thinking not lead to something like, if you drink more water, it'll end up diluting your blood and you'll die because of that. Nope, nothing could be far from the truth. Nothing that we eat or drink can or could end up directly in your blood. Survival would be impossible if that were true.

The nutrients are broken down in the digestive tract to their smallest components and then sent to the liver for re-packaging. By re-packaging I mean, that the liver uses these base components to make new stuff out of. What we consume does affect this re-packaging process. A scientific fact, that doctors are aware of is, that if the liver finds less fats in what you eat, it makes more fats out of the other stuff. Didn't you think that the body had it's own intelligence ? 

The lipids that we get evaluated for in the blood tests are approximately affected 85% by the body's own fats production and 15% by the fats in your diet. The 85% fats in blood come from our own bile juices. The 15% dietary contribution is also a vague estimate, it could be more like 10%. Wouldn't it be a better idea to control the 85% and not the 15%. That's why the lipid hypothesis which says the more fats you eat, the more fats you have circulating in your blood is completely wrong. It's the excessive carbohydrates in the diet which cause the liver to re-package more fats in your blood. 

It's not the fats silly.
-----

Nobody ever said that the body makes only fats and not proteins or the other stuff. It makes everything that is needed, in the quantity needed, and when it is needed. Every part of the body works to maintain ‘homeostasis’ – a state of balance within. The problems start when this homeostasis is disturbed.

The vitamins are not made in the body but come from diet. They are used as catalysts in (1) further synthesis of other substances and (2) in the actions of several enzymes and co-enzymes that the body uses in diverse functions. Proteins are what we are made up of, as are all organisms, including bacteria and viruses. Every cell uses it’s genetic code within the DNA to continuously make proteins that are required in body for build-up, repair and many other functions.

Our blood supply vessels are lined with a protective inner layer known as the endothelium. Due to chronic inflammation or for some other reasons as well, the endothelial cells do get compromised and lesions start to form. What causes chronic inflammation within the blood vessels – High levels of insulin. What causes high levels of insulin – High levels of glucose. What causes high levels of glucose – High levels of carbohydrates in diet.

So when the endothelium is damaged and lesions appear (cracks form up), the smaller, denser lipoproteins (mostly sdLDL or Lp(a)) are attracted to the injured portions and enter deeper into the artery for repair to the damage. Once trapped inside the intima (the internal layer) of the vessel, the cholesterol within the lipoprotein carriers gets oxidized by the action of free radicals. Free radicals are any type of molecules with unpaired electrons, which are always looking to join up and react with something or the other. This sets off a chain reaction as more and more of the cholesterol gets oxidized and begins to decay.

Here, the protective Immune system is asked to step in and respond to the threat/injury. Monocytes which are a type of white blood cells, meant to fight infection are sent in for the defence. Monocytes enter the damaged tissue through the endothelium. They undergo a series of changes in their action, to become a macrophage. The role of macrophages is to engulf and then digest the cellular debris or the pathogens. When they become loaded with the cholesterol debris they acquire a bloated appearance and are now known as Foam cells.

Our body’s intelligence knows that in the vascular interiors, debris if offloaded into the circulation, may end up blocking some smaller vessel, somewhere. If that happens in the brain, you’d get a stroke. If it happens in the heart, you’d get an attack. So not taking that chance, the endothelium grows back over the foam cells deposited within, thus creating a mound within the blood vessel. Such damaged portions are then vulnerable to further attack, and over time the passage could become narrower and narrower. These are commonly referred to as “blockages” by heart surgeons. The reason why this happens only within certain arteries surrounding the heart which supply blood to the heart muscles is that because the blood gushes through these arteries under tremendous pressure and there are a lot of turns & forks in these arteries.

And when that happens, the blood supply gets restricted causing all sorts of problems. So the automatic question that follows – Is it the fats in the blood that are responsible for this damage. The correct answer is Yes & No. Yes because it is the fats within “some” of the LDL that get oxidized. And No, because it is the endothelial dysfunction that opens up the intima in the first place. Again, to control the serum fats, should we target the fats in our diet – Again Yes & No. Yes because there are ‘good’ fats and ‘bad’ fats, so obviously you have to choose well. And No because the fats in diet have no relation to the fats in blood serum. More fats are created and enter circulation when you eat a high carbohydrate diet.

So in a very nice circle, we have come back to – It’s not the fats silly.
-----

The question of fats in diet & fats in blood is so complex that it is very difficult to answer it in totality, while at the same time trying to keep the matter simple and understandable by everybody. Nevertheless a few points in a rejoinder were necessary and so here we go ...

Firstly it is important to note that when the endothelium is damaged and opens up to allow entry within, it's not just the lipoproteins that can enter and the fats within these lipoproteins that can cause damage. A whole lot of other stuff also can and does enter and do it's dirty work. Most known among these are calcium and some other minerals. And all of them are susceptible to further action of free radicals.

Further, in defence of dietary fats, it should be told, that most of the fats absorbed in the intestines through diet are too large in their composition to directly enter into circulation. Therefore they are packaged within larger lipoproteins known as "chylomicrons" and are sent into the lymph for circulation and delivery. The lymph is the other form of circulatory system within our body which is not completely enclosed as the cardiovascular (blood supply) system.

Chlyomicrons have a very short half life of a couple of hours and they enter into the CV supply  via the thoracic duct, somewhere near the neck. By that time they have lost most of their goods (cholesterol & TGs) and are much smaller in size and enter the CV system as vLDLs. This short life is the reason why a 12 hour fasting period is required when taking the lipid count in your blood tests. The chylomicrons, IDLs & vLDLs are mostly out of the way by then.

The fats that are packaged within lipoproteins in the liver mostly come from our own bile juices and leave in the form of vLDLs & LDLs. That is why we say that body makes it's own fats in a much larger proportion (approx 85%) than dietary fats.

I also want to add a disclaimer here. I started eating the way I do about 3 years ago and over these years have decreased my carbs & increased my fats. Assuming that this is the right way to eat, I could now potentially be preventing any inflammation and further damage within my CV system. But that does not erase 52 years of damage that I brought about in my system prior to this. Mounds / blockages once formed within arteries might not be reversed. The only way of tackling that problem is by either putting in a "stent" to increase the diameter of the artery or going in for a by-pass if the blockage is too severe. I have to live the rest of my life with that knowledge and hope that the past damage is not too severe to cause any future problems.

Another notable fact is that there are many risk factors where heart disease is concerned. Age is the foremost amongst them. As we age our functions and organs weaken and we are in a vulnerable stage. Added to that is the fact that by then the growth phase is over and we are now losing more cells than we are making. For no rhyme or reason, we blame the poor fats. They have so many important roles in the body No fats = no life, yet they take a solid beating time and again. As a matter of fact, it is the cholesterol in us that makes us animals different from plants and gives us mobility.

It’s not the fats, silly.

No comments:

Post a comment