Are saturated fats and cholesterol the causes of coronary heart disease?
Practically all doctors and nutritionists tell us that the causes of coronary heart disease are saturated fats and cholesterol. And so they constantly tell us to cut down on our consumption of saturated fats and cholesterol.
This idea is so widely accepted and deeply entrenched that few people dare to question it.
Even those who campaign against trans fats, and tell us that trans fats are the real causes of coronary heart disease – as well as many other health problems including diabetes, obesity and various types of cancer – usually advise us further that we should also cut down on saturated fats and cholesterol.
This idea is called the lipid hypothesis or diet-heart idea. It has dominated medical thinking about heart disease for the past 50 years.
According to this idea, when we eat foods rich in saturated fat and cholesterol, these substances get deposited in our arteries in the form of plaque. Over time, the plaque builds up, causing our arteries to get narrower and narrow until one day, little or no blood can pass through.
Or, a blood clot forms and cannot get past the narrow space created by the build-up of plague. Thus, a heart attack occurs.
This seems to make sense. And so the lipid hypothesis gained tremendous popularity. What’s more, it is supported by some 50 years of scientific research that “prove” that saturated fats and cholesterol are the causes of heart disease.
The only problem with this diet-heart ideas, however, is that it does explain what happens in real life.
Plaques are the causes of coronary heart disease
Many distinguished scientists have pointed to serious flaws in this theory about the causes of coronary heart disease.
For example, studies of different populations show that most older people had build up of plaque in the artery, or atherosclerosis, whether or not they had heart disease. For example
who eat fairly substantial amounts of meat and saturated fats, were
found in a 1955 study to have significant plaque build up. This study
made front page newspaper headlines, and reinforced the idea that
saturated fats were the causes of heart disease.
who ate little meat compared to the Koreans, were also found to have
significant plaque build up in their arteries. This study was done at
about the same time but it did not make the front page headlines.
- The Bantu, a South African tribe whose diet was largely vegetarian, were found to have as much plaque buildup in the arteries as other South African tribes who ate more meat.
- Blacks in Jamaica had as much atherosclerosis as Americans, but they had lower rates of heart disease.
- The Masai, an African tribe whose members eats only meat, blood and milk and have extremely high levels of saturated fats in their diet, have practically zero heart disease. They also have one of the world’s lowest levels of blood cholesterol.
One of the biggest studies to establish saturated fats as the causes of coronary heart disease was the 1968 International Atherosclerosis Project, in which over 22,000 corpses in 14 nations were cut open and examined for plaques in the arteries.
The study found roughly the same degree of plaque in all parts of the world – among people who ate a lot of meat as well as those who ate little or no meat; among people with high rates of heart disease as well as those with little or no heart disease.
Saturated fats are not the causes of coronary heart disease
The theory that saturated fats and cholesterol causes heart disease fail to explain other real-life observations as well.
- In America,
the rate of heart disease soared during a period when saturated fats
consumption fell sharply while cholesterol intake remained roughly
Before 1900, heart disease was rare in America, affecting about 8 percent of the population. By 1950, heart disease caused 30 percent of all deaths in America. Today, it causes about 45 percent of all deaths.
During the period, consumption butter, which is high in saturated fats, fell from over 18 lbs per person per year at the turn of the century, to about 10 lbs per person per year by 1950. Today it is even lower, yet the rate of heart disease continues to escalate.
In the same period, Margarine consupmption rose from about 2 lbs per person at the turn of the century to about 8 lbs per person.
If saturated fats are the causes of coronary heart disease, one would expect the rate of heart disease in America to fall over the past 100 years, rather than to increase so dramatically.
“The diet-heart idea is the greatest scam in the history of medicine.”
– George Mann
The same heart disease patterns have taken place throughout the world in more recent decades. Everywhere, whenever the population reduces its consumption of saturated fats and switched to polyunsaturated vegetable cooking oils, the rate of heart disease started soaring.
- In India, a
1968 study found North Indians, who ate more meat and used mainly ghee
(clarified butter) for cooking, had 17 times more saturated fats in
their diets than South Indians, who were more vegetarians. However,
North Indians had seven times less heart disease than Indians in the
This was because, by the late 60s, South Indians had started the switch from coconut oil, which contains about 90 percent saturated fats, to margarine and other polyunsaturated vegetable oils.
More recent studies show that North Indians are finally begin to catch up with the South in heart disease rates – because North Indians have started to use less ghee and more margarine and vegetable oils.
Causes of coronary heart disease in modern times
Before we examine what are the true causes of coronary heart disease, there is another very important point to note: Modern heart disease is a new form of heart disease that did not exist before 1900.
Most people who die from heart disease nowadays die from myocardial infraction, or what is commonly called a heart attack. This happens when a massive blood clot causes obstruction of a coronary artery and consequent death to the heart muscle.
Apart from heart attacks, another common cause of death today is stroke. In a stroke, the same thing happens – a massive blood clot blocks the flow of blood, except that it occurs in the brain!
Myocardial infarction, or heart attack, almost never occurred before the 1920s. By 1930, it caused about 3,000 deaths in America. Today, it causes more than 500,000 deaths in America each year.
Dr. Paul Dudley White was the man who introduced the electrocardiograph (ECG) machine –a device for studying heart beats – to America during the 1920s. The ECG was a new German invention at that time. And heart disease was so rare that Paul Dudley White’s medical colleagues advised him to find a better way to earn a living.
In a 1956 television interview to raise funds for the American Heart Association televised, Paul Dudley White said: “I began my practice as a cardiologist in 1921 and I never saw a myocardial infraction patient until 1928.”
Two causes of coronary heart disease
This background about myocardial infraction is important for understanding the true causes of coronary heart disease in modern times. It tells us that at least two conditions must be present before a heart attack or a stroke can take place:
- The build-up of abnormal plaque in the arteries. This abnormal plaque gradually hardens through calcification and it occurs most often in the large arteries feeding the heart or the brain.
- The blood clot – which doctors call thrombus – that blocks blood flow to the heart or brain.
Causes of coronary heart disease – ABNORMAL plaque
The build-up of abnormal plaque is therefore just one of at least two causes of heart disease. Yet the majority of doctors and scientist focus on this one factor, ignoring or paying scant attention to other causes of coronary heart disease.
The word ABNORMAL has to be emphasised. Earlier, we saw that people all over the world tend to have plaque build-up in their arteries no matter whether they:
- ate plenty of meat products of were largely vegetarian
- lived in traditional or industrialised societies
- had high rates of heart disease or little or no heart disease.
Thus, plaque build-up, on its own, is not one of the causes of coronary heart disease.
This NATURAL plaque build-up is a protective factor. They occur mostly in areas where the arteries might come under stress, such as places where they branch out or make a turn. Without this protective plaque build up, our arteries would weaken as we grow older. They might rupture.
With normal plaque build up, the blood vessels usually widen to accommodate the change. So blood continues to flow smoothly, unobstructed.
This natural plaque build-up is due to saturated fats and cholesterol. It is not a problem. It is not a symptom of heart disease. Saturated fats and cholesterol are not causes of coronary heart disease.
Many possible causes of coronary heart disease
Heart disease starts to develop only when the plaque build-up is ABNORMAL – meaning it is thicker and harder than normal, and it deposits in areas where normal plaque do not normally occur.
Why does this happen? No one knows for sure and there are many theories to explain this abnormal plaque build-up. These various theories give us a better idea about the true causes of coronary heart disease.
The predominant theory is that abnormal plaque build-up occurs due to damage or injury to the arteries. To repair the damage or injury, the body deposits saturated fat and cholesterol to patch up the area.
Causes of coronary heart disease – Blood clots
To discover the causes of coronary heart disease, scientists must understand what causes blood clots inside the arteries. This aspect has not received adequate attention from researchers.
But it is equally important. A heart attack due to a clot can occur when the arteries are not blocked by abnormal plaque build-up.
Here again, there are many theories and possible explanations:
- Inflammation is one of the possible causes of coronary heart disease. Normally, inflammation is a natural process that helps the body heal from injury. But with dmage and injury occurs too often inside the arteries, inflammation might cause plaques to rupture and blood clots to form.
- Integrity of artery walls is another factor. When the vessel walls are weak, they might break or tear. This will not only cause blood clots, but also rapid loss of blood.
Many causes of coronary heart disease
What causes damage or injury or blood vessels – which lead to abnormal plaque build-up, inflammation, ruptures, blood clots… leading to a heart attack?
Here is where the many different theories come in. Among many possible causes of coronary heart disease, they could be due to:
- trans fats
- free radicals
- oils that have turned rancid and oxidised – due to high heat or exposure to oxygen and light
- sugar and other refined carbohydrates
- excess omega-6 from refined vegetable oils
- viral or bacteria infection
- nutritional deficiency, including deficiencies of vitamins A, C and E, folic acid, vitamins B6 and B12, selenium, magnesium, etc
- pasteurised and UHT treated milk
- thyroid malfunction
- coffee consumption
- lack of exercise
- exposure to carbon monoxide
Most of these theories provide better explanations – and have stronger supporting evidence – than the popular lips theory that blames saturated fats and cholesterol as the causes of coronary heart disease.
Is smoking one of the causes of coronary heart disease?
Smoking, too, is often cited as one of the major causes of coronary heart disease. But does smoking really cause heart disease? This idea, too, needs to be seriously examined.
- In a long term British study involving several thousand men, half of them were asked to reduce saturated fat and cholesterol, stop smoking and increase the amounts of unsaturated oils such as margarine and vegetable oils. The rest continued to eat their usual amounts of saturated fats and cholesterol, and also continued to smoke.
The study results, reported in The Lancet in 1968, were startling: After one year, those following the ‘healthy’ diet and lifetyle had 100 percent more deaths than those on the supposedly unhealthy diet and lifestyle.
- A study of Indians from Bombay and Punjab found that those from Punjab had one-fifth the number of heart attacks even though they smoked eight times more cigarettes!
Most signficant is the fact that smoking was widespread – just as saturated fats were widely consumed – at the turn of last century, when heart attacks were non-existent.
There are several possible explanations for this:
- Factors in traditional diets – including possibly saturated fats – could have protected against the negative effects of smoking
- Chemical additives in modern cigarettes – in the tobacco as well as in the paper – make them more harmful
- Both heart disease and the desire to smoke are caused by some other factors, such as stress, nutritional deficiency, etc.
Causes of coronary heart disease – lack of physical activity
The causes of coronary heart disease are therefore not as straight forward as most doctors and health authorities make it out to be.
This discussion can go on and on… But let’s end off for now with one of the more straight forward causes of coronary heart disease – lack of exercise or physical activity.
When we exercise or perform physical activity, our heart beats more rapidly and the arteries widen to facilitate blood flow and provide more oxygen to the cells.
Lack of exercise may also point to other factors that may be the true causes of coronary heart disease. For example, people who are overweight tend to dislike exercise. Or, certain foods may make people feel lethargic and less inclined to exercise.
For now, let’s end off with another food for thought…
The Framingham Heart Study, started in 1948 and still on-going, is one of the biggest research projects on heart health. In 2002, study leader Dr William Castelli wrote in Archives of Internal Medicine:
“In Frammingham, Massachusetts… the people who ate the most cholesterol, ate the most saturated fat, ate the most calories, weighed the least and were the most physically active.”