A Statin Nation. Dr Malcolm Kendrick
and is sometimes called fat, as in ‘triglycerides are fats’.
Notes
1. https://www.westonaprice.org/health-topics/know-your-fats/the-tragic-legacy-of-center-for-science-in-the-public-interest-cspi/
DIAGRAM 13
In this chemical diagram of a triglyceride, we have two saturated fatty acids at the top of the triglyceride and one monounsaturated fatty acid at the bottom with a -cis bond. You can have any combination of fatty acids in a triglyceride. One saturated and two monounsaturated, all monounsaturated, all polyunsaturated, etc.
There are a few other things you need to know about triglycerides. Because the acidic end ‘COOH’ is now bound to glycerol, a triglyceride is not acidic, it is Ph neutral, neither acid nor alkali. Of additional interest, the backbone of a triglyceride is a glycerol molecule, and each glycerol molecule is one half of a glucose molecule. When triglycerides, stored in fat cells, are broken down to release the fatty acids into the bloodstream, glycerol molecules will also exit and travel to the liver, where they combine to make glucose. This means that, even on a zero-carbohydrate diet, you still end up with some glucose in the bloodstream.
Clearly, the other breakdown products of triglycerides are fatty acids. When these enter the bloodstream, they are called free fatty acids (FFAs), which are the preferred energy source for many organs. In fact, the heart runs almost exclusively on free fatty acids.1
When FFAs reach the liver, they will be absorbed and, if the insulin levels are low, will automatically be broken down into smaller ketone bodies, which are a substitute for glucose in many organs – some would say they are preferred to glucose.
DIAGRAM 14 – KEYTONE BODIES A STATIN NATION
When blood glucose levels are low, the brain receives 60–70 per cent of the energy it needs from ketone bodies. The heart will also use ketone bodies, alongside FFAs, for energy rather than glucose, as do many other organs.
This preference for ketone bodies over glucose should not really be surprising. The body can store, literally, millions of calories as triglycerides/fatty acids, and only around 1,500 calories as glucose/glycogen. Ergo, the body must be perfectly adapted to use fatty acids and ketone bodies for energy or it could not function. Bears in hibernation, for example, have no choice but to live off fat stores for up to six months, and it does them no harm, although they get a bit grumpy when they wake up.
You do not need to get into such an extreme metabolic state as hibernation before your body stops using glucose as the primary energy source. After fasting for a day, your glucose/glycogen stores will be running dry. Then your metabolism happily switches over, at which point you enter the state of ketosis, which simply means that the body is using mainly ketone bodies for energy. Some of the ketone bodies can escape from the lungs, and this leads to funny-smelling breath. In addition, as both ketone bodies and FFAs are mild acids, your blood will, in turn, become more acidic.
Does this matter? Wild claims have been made that this acidity will damage and destroy your kidneys, and cause bone damage. The most outrageous claims are usually made by fundamentalist vegans. The reality is that I have not seen any strong evidence linking ketosis to significant adverse health. But there is some evidence that continuous, lifelong ketosis may create problems in a few individuals.2 On the other hand, people with resistant epilepsy have found that ketosis will often ‘cure’ their disease. This is well accepted and non-contentious. But most people are never going to remain entirely carbohydrate-restricted year after year, and I would not recommend this unless you have intractable epilepsy. There are some who do, and those who follow the anti-carb ‘paleo’ diet would have us all ruthlessly expunge carbohydrates from our diet and eat virtually nothing but animal products.
Why, oh why, do people have to go to such extremes? I am fully on board with eating natural foods and drastically cutting down on the carbs, especially if you have diabetes. But you don’t need to go completely bonkers. Our ancestors ate fruit and nuts, and whatever vegetables they could find. We are not designed to be carb-free, nor should we try to be.
Another problem is that people mix up ketosis and ketoacidosis. They sound similar, but they are not the same. One is perfectly healthy, one deadly. Ketosis occurs in anyone who doesn’t eat for a day. Ketoacidosis will only occur if you have type 1 diabetes, the type of diabetes when the body cannot produce insulin.
Insulin, amongst other things, keeps triglycerides trapped in fat cells. This is because insulin is primarily an energy-storage hormone, and one of its roles is to ensure that fatty acids are stored, not released. If the insulin level drops too low, and stays low, triglycerides break down into FFAs and then flood out into the bloodstream. When they reach the liver, they are automatically converted to ketone bodies, and this unstoppable avalanche will turn the blood more and more acidic until you enter a keto-acidotic coma. And you die.
Ketoacidosis, ketosis. Do not get these very similar terms confused. But if you do, you will be in good company, alongside 90 per cent of medics who hear ‘keto’… then run, screaming in terror. Straight to the nearest McDonald’s.
Anyway, at this point, I hope that you have a better handle on what fatty acids are, and how they fit into the human metabolism, and how to understand the terminology surrounding fatty acids, etc. Unfortunately, there is one further area of potential confusion that I need to clarify, which is the word lipid. You may have heard of blood lipids or lipid levels. Are they the same as fats/fatty acids?
To quote Medicine.net on lipids: ‘Lipids: Another word for “fats”. Lipids can be more formally defined as substances such as a fat, oil or wax that dissolves in alcohol but not in water. Lipids contain carbon, hydrogen and oxygen but have far less oxygen proportionally than carbohydrates.’
Yes, fats can be called lipids and lipids are fats. The two words are interchangeable. Just to make things clear, here is my little ready reckoner:
Fatty acid = fat
Triglyceride = fat
Lipid = fat
Fat = lipid
Clear? The unfortunate fact is that, in this area, people interchange terminology all the time. This does not make it easy to follow what they are talking about. In fact, I often wonder if they have any idea themselves. At least now, I hope, you have a good grasp of this whole area.
Notes
1. https://www.ncbi.nlm.nih.gov/books/NBK22436/
2. https://www.ncbi.nlm.nih.gov/pubmed/28030918
Конец