The real truth about cholesterol You go to your doctor for a check-up. He finds your cholesterol is high. What does he tell you to do? Eat healthy. What does eating healthy mean? It usually means cutting out fat and eliminating eggs from your diet. Or if you must eat eggs, consume only the whites and cut down on the yolks, in fact it’s better to do away with them entirely.
This low-fat, low-cholesterol diet advice has been dispensed for over four decades now. In the 70s and the 80s, it was almost unchallenged. The evidence seemed so overwhelmingly in favour of cutting out fat from our diet. We did, and we continue to do so and yet our disease burden has not become any lighter over the years. So, we feel it is time to ask ourselves whether we got the cholesterol story right. People with very desirable cholesterol levels die every day from sudden death or sudden unforeseen, unpredicted heart attacks. Doctors who only weeks before had given them a check-up and concluded there was no risk because cholesterol was normal are baffled when this happens.
In our experience, we have come to realise that measuring cholesterol alone gives no indication of what may happen in terms of a heart attack, because, cholesterol is not a great predictor of a heart attack.
Thanks to a questionable observational study called Seven Nations by Ancel Keys, the myth of dietary cholesterol as being bad for health was born in the US and took firm root by the 70s. In that study — which was to shape the dietary habits of a whole generation of people in most parts of the world — Keys studied the diet in Northern Europe, Southern Europe and Japan. He drew the conclusion, proved wrong since then in multiple studies, that fat consumption caused greater heart disease risk. He concluded that dietary fat and cholesterol were equal to body cholesterol. Thus the great myth of cholesterol was born and with the help of the US Food and Drug Administration and its famous Food Pyramid advice to general population, the war on dietary fat was waged.
Cholesterol became public health enemy number one. Whether you really were at risk or not, you were medically advised to take a medication or do something about that cholesterol. With such a public awareness and doctors routinely testing for cholesterol and writing prescriptions, heart disease should have come down. It did not. It should have been a war won easily. It wasn’t.
What actually happened?
Why is the fight against heart disease not being won?
Unlike in the 60s and 70s when we did not have all the molecular knowledge and the laboratory tests to understand how heart disease actually develops, we now have a substantial body of clear evidence to show that the popular dietary advice of the last four decades has been faulty. Study after study has proven the absence of a link between dietary cholesterol, fat and heart disease. If anything groups that consumed pure fat and high protein and limited amounts of carbohydrates have repeatedly been shown to have a much better cholesterol profile than those who adopted a high-carb, low-fat diet. Anyone interested in the dietary fat/heart disease myth should read American’s science writer and nutrition explorer Gary Taube’s excellent Good Calories, Bad Calories. In this book, he presents his case for refined carbohydrates being the biggest culprits for bad health.
To understand how we continue to propagate the falsehood that dietary cholesterol kills, you only need to ask how cholesterol is formed. You will be surprised to know that your body is capable of making all the cholesterol it needs even if you ate a cholesterol-free diet. In fact most of the cholesterol in your body is made by the liver. And what may be even more surprising to you is the fact that cholesterol can only be made when you have eaten carbohydrates (bread, pasta, rice, potato, etc). It is not made from fat or the cholesterol in the eggs.
Two things are essential in making cholesterol: Glucose derived from carbohydrates and the hormone insulin released by the pancreas in response the arrival of glucose. Without these, little cholesterol can be formed.
So it can now be seen why despite the warnings about removing fat and cholesterol from one’s diet, cholesterol levels in people have not come down. The more carbohydrates you eat, the more likely your cholesterol levels will go up.
And that is exactly what happened in the 70s, 80s and 90s when the benefits of a low-fat, high-carbohydrate diet were promoted and heart disease, diabetes rose and blood pressure rose.
The other surprising thing is that cholesterol drugs do not do anything to dietary cholesterol. These drugs work bypreventing the formation of cholesterol from mainly carbohydrate derivatives. So, to understand why carbohydtaes play such a huge role in the way cholesterol can form in our bodies, here is the process: All food that we eat, whether protein, fat or carbohydrates, is broken into a two carbon-molecule called Acetyl-CoA. It is from Acetyl-CoA that cholesterol is formed through a series of biochemical reactions that lead to the formation of another intermediate compound called HMG-CoA. Now, while protein and fat produce Acetyl-CoA, both do not require the release of insulin from the pancreas, so the Aceyl-CoA from them will not help in the formation of cholesterol. And insulin is pivotal in the making of cholesterol by the body. So, if protein and fats do not trigger an insulin release, what does? Carbohydrates. Only carbohydrate foods trigger insulin release thus helping the body make cholesterol.
So when you take a cholesterol-lowering drug, the drug does not work on the cholesterol contained in the food but it works by blocking the crucial biochemical step at HMG-CoA. If there was no Acetyl-CoA coming from the breakdown of carbohydrates, the Acetyl-CoA from protein and fat undergo a different fate and in the absence of insulin, will not be able to form cholesterol.
Thriving on fat and eggs
The premise that dietary cholesterol raises blood cholesterol levels proportionately is easily proven wrong. There are plenty of studies in which two groups were fed two different diets — one high-fat, high-cholesterol and another low-fat, high-carbohydrate. Not one study showed the group which ate the high-fat diet had raised cholesterol levels. In fact, the surprising finding in many of these studies is that the so-called good cholesterol HDL actually goes up on a high-fat and high-protein diet.
If the theory that a diet rich in animal fat and protein was right, then cardiovascular disease should be alarmingly high in communities which eat mostly fat and protein. The best examples are the Inuit Eskimos and the Masai tribes in Africa. The Inuit consume mostly seal fat and meat while the Masai live on full-fat milk, cow blood and meat. When they should be expected to have high incidence of heart disease based on our current dietary guidelines, they in fact have the lowest comparable risk.
Fat as a prized commodity historically
Historically, every nation and community valued dietary fat. You will find not a single reference anywhere in historical writing on diet and nutrition that fat was bad. Fat was a prized commodity. We lived on animal fat and whatever we got from nuts and seeds naturally. And heart disease was low. Countries like France and Belgium still use butter as a preferred cooking medium. Heart disease in these countries is not higher as should be expected.
The egg myth
The idea that eating eggs raises blood cholesterol levels has no basis in fact or science. If this idea were to be true, then a person who eats three or four eggs a day should have a high cholesterol level after two or three months. The most famous proof to the contrary was provided a few years ago the Danish independent researcher and former private medical practitioner Dr Uffe Ravnskov, who wrote on the myths of cholesterol in his book The Cholesterol Myth — Exposing the Fallacy that Saturated and Cholesterol Cause Heart Disease. Ravnskov is well-known in the medical fraternity for his relentless questioning of the standard approach to the role of lipids in the blood. During an experimental period lasting several weeks, he gradually increased the number of eggs eaten daily to eight per day. His cholesterol should have sky-rocketed. It actually dropped from 278mg/dl to 246mg/dl.
Eggs are one of most nutritious and inexpensive protein-rich foods. But most families have banished this wonderful food from their diet because the dietary establishment and the medically community have been proclaiming loudly how bad they are to your heart.
Which type of cholesterol kills?
Nearly half of all heart attacks that occur in people have cholesterol levels that are normal or borderline. Their arteries are not clogged.
What happened with them? Why this apparent contradiction? The problem starts when the LDL cholesterol goes through a process called oxidation. Oxidation reactions are part of normal metabolism when oxygen-free radicals are formed. These are oxygen molecules have one less electron than is needed for them to be stable. It is these unpaired oxygen molecues that attack healthy cells or other biological molecules and change their behaviour. Free radicals can attack LDL and oxidise them.
When a molecule is oxidised, it gains an oxygen electron or loses a hydrogen. The oxidation of LDL starts a chain of inflammatory processes. These processes lead to the formation of foamy substances that evolve into the dreaded plaque. Because we have been so pre-occupied with cholesterol as a whole, we have often been missing the target in identifying the people at risk of heart attacks. If nearly 50 per cent of heart attacks happen in people who do not have the generally accepted risk factors including high cholesterol, why are they dying? It so happens that the oxidation of LDL particle can take place irrespective of cholesterol being high or normal.
You can check your oxLDL levels by going to molecular labs such as Diagnostika in Dubai Biotechnology Park. What will this help you do? If your cholesterol is normal but you are showing high levels of oxLDL, you would need to worry and start taking medicines to reduce oxidation and stabilise the plaque within your arteries. On the other hand, if you cholesterol is high but there is no evidence of oxidation, you may want to have your dietary intake analysed.
So in other words, there is more to typical Total Cholesterol stats. At the molecular level, the oxLDL is a huge determining factor for risk. There is no formation of arterial plaque unless the LDL has been first oxidised. So a person can have high cholesterol but no disease risk if there is no oxidation of LDL.
If there is a family history of heart disease, get yourself checked for heart disease-related genetic risks. This can be done from a simple saliva sample. They should also get an advanced evaluation done for metabolism, free radical activity levels, PAI-1, oxLDL, etc.
When it comes to your diet, all refined and processed foods are the true villains. Remember, all other species on this planet regulate their food intake naturally. It’s only human beings who overeat without reason. Also, it would be useful to remember that overeating happens primarily with simple sugars and refined, ultra-processed carbohydrates.