Far from being limited to developed nations, up to 80% of cases occur in developing countries. In fact, a staggering 60% of the world's cardiovascular disease is estimated to occur in India alone.
Smoking, high blood pressure, and cholesterol are the usual suspects. In fact, the association between cholesterol and heart disease is firmly fixed in most people's minds.
Heart disease is known to be triggered by atherosclerosis, a hidden chronic condition that affects the walls of arteries and can be present for decades before any clinical symptoms appear.
Atherosclerosis can damage or kill heart cells and lead to sudden death by heart failure. Understanding what triggers this invisible danger and how it develops is critical step to prevent it from happening.
Interestingly, studies have shown that with the right dietary and lifestyle interventions, atherosclerosis can in fact be reversed in most people!
So - do blood cholesterol levels cause atherosclerosis and heart disease?
Let's briefly consider the human heart - a muscular, 4-chambered organ the size of a fist, weighing some 250-350 grams and located behind the breast bone. It pumps blood throughout the body by contracting rhythmically in a specific sequence - check out this cool animation of how the heart works.
Our hearts function in this complex manner 60 to 70 times every minute, roughly 36 million times every year of our lives! Now that is a true miracle, and not an insignificant one at that...
Arteries are blood vessels that carry oxygenated blood from the heart to all parts of the body. When healthy, they are strong and flexible and can easily cope with the constant changes in blood pressure that happen when your level of physical activity changes, or you change position such as getting up from being seated or lying down.
Arteries that supply the heart muscle are called coronary arteries.
Atherosclerosis is the buildup of a fatty material called plaque on the inside walls of arteries, a slow and insidious process that takes place over many years. These plaques or lesions are made up of fat, cholesterol, calcium, white blood cells, muscle cells and scar tissue.
Plaques make arteries stiffer and less elastic, which means they are more likely to get damaged with constant changes in blood pressure. The lumen - the inner space through which blood flows - becomes narrower, restricting blood and nutrient flow to tissues.
Narrower arteries also means that more blood pressure is needed to pump blood and the heart has to work harder.
If these dangerous plaques form in coronary arteries, blood flow to the heart itself is affected. The heart needs a steady supply of oxygen to work properly. When blood flow to an area of the heart decreases, that part functions less efficiently, affecting overall heart function.
Atherosclerotic plaque formation in coronary arteries is a critical first step necessary for life-threatening heart attacks to happen.
In adults, high levels of the "bad" cholesterol known as low-density lipoprotein or LDL cholesterol, low levels of the "good" cholesterol known as high-density lipoprotein or HDL cholesterol, hypertension, smoking, metabolic syndrome, diabetes and obesity are all associated with a high risk for atherosclerosis.
According to the US National Institutes of Health (NIH), high levels of cholesterol are responsible for plaque formation, and by implication cause heart disease.
This view is propagated as gospel by much of the medical establishment, regulatory agencies and drug companies.
There are 2 major flaws in this argument.
FIRST - there is plenty of evidence to show that atherosclerosis is not triggered by cholesterol, although it contributes to plaque buildup.
In fact, several studies have shown that there is zero correlation between cholesterol levels and atherosclerosis! (More on this in a future post).
In other words, the popular association between heart disease and cholesterol is a mythical one. So why do the medical establishment and drug companies still propagate this imaginary association?
Good question.
Let's consider the evidence.
Dr. Dwight Lundell is a leading cardiovascular surgeon who has performed over 5,000 heart surgeries. He states bluntly, "Dropping your cholesterol levels will not lower your risk of heart disease, heart attacks, or strokes".
That's pretty straightforward, isn't it?
Dr. Michael Ozner, MD, is the author of The Great American Heart Hoax, a fascinating book about what actually works to prevent heart disease.
Based on his extensive personal experiences with heart disease patients, he's firmly convinced that chemical oxidation of LDL cholesterol is one of the first steps in atherosclerosis.
Oxidized LDL cholesterol is very reactive and attacks the muscle cells that make up artery walls. Over time, our body’s inflammatory response to such repeated attacks and the injury that follows triggers atherosclerotic plaque formation in arteries.
In other words, he believes there is no association between heart disease and cholesterol levels.
SECOND - heart attacks are not caused by the plaques themselves.
According to Dr. Lundell and other experts, the real culprits are clots created by our body's own protective mechanisms when unstable plaques occasionally rupture.
Over time, these clots detach and flow freely in the blood. They may move downstream into smaller blood vessels and obstruct blood flow, causing angina or heart attacks.
Angina is the pain or discomfort that occurs when not enough oxygen-rich blood is available to heart muscle. Heart attacks happen when the blood flow is completely blocked. Lack of oxygen can cause heart cells to die within 5 minutes.
The take-home message is this - blood levels of cholesterol are not the trigger for atherosclerosis, which causes angina, heart attacks and strokes.
Yet the pharmaceutical industry makes millions of dollars every year by prescribing cholesterol-lowering medications such as statins and other drugs to people in so-called "high-risk" groups. Nowadays these drugs are even being prescribed to ordinary people whose cholesterol levels are judged to be "too high".
Since blood cholesterol levels are not the trigger for heart disease, these medications are not very effective against heart attacks and - as evidence shows - possibly even downright harmful to human health.
Don't get me wrong - I'm not saying that high cholesterol levels are good for your heart, they aren't. But in an average human being with a physiological range of cholesterol levels, they are not the trigger for heart attacks.
The real cause, as we shall explore in another post, is something else - inflammation, which underlies many aspects of human disease including oxidation of LDL cholesterol, the first step in atherosclerosis.
And unless inflammation and its causes are specifically addressed, nothing - no medication available on the market today, or expensive invasive procedures such as angioplasty and coronary bypass surgery - will reduce your risk of a first or recurrent heart attack.
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