What is the cause of heart disease?
Now that’s an interesting question, wouldn’t you agree?
Trust me I have a concern about heart disease because it is hereditary in my family. My grandmother had angina from very young and died at just 59, my grandfather died of a massive heart attack at 62, that’s pretty young too. And the line of heart disease goes back beyond that too, at least on my mothers side. So heart disease is a concern for me, I just wanted to say that before delving into this article because what I’m about to share may be quite different to the information you’re used to hearing about heart disease.
Now, one of the things that many of us have been told is that heart disease is caused by cholesterol that clogs our arteries. We’ve seen pictures like this:-
And we’ve been told that fat we eat clogs our arteries and leads to heart attack and stroke.
Like you, this is what I also believed for many years, it’s common knowledge, we all know that’s the case, right?
Heart Disease Is Not Caused By Cholesterol!
I’m not going to go into the topic of cholesterol right now but what I will cover is what I know to be true about heart disease. You may ask, why should I listen to you? Well, you don’t have to, but I have been researching cardiovascular disease (heart disease) in my Masters thesis and have discovered a thing or two about it that I think you should know too.
Heart Disease is an Inflammatory Condition
Atherosclerosis is the predominant underlying problem contributing to the rate of angina, heart attack and stroke. When it comes to heart disease, angina, heart attack, and stroke are the things that will most likely kill you. Essentially atherosclerosis is your arteries getting blocked, that part of common knowledge is true. As stated earlier high cholesterol and the accumulation of lipids (fats) within the artery wall was long considered the leading cause of heart disease. I won’t tell you the story of how that came about, we’ll share that another time.
What you need to know is that high cholesterol and the accumulation of lipids (fats) is not the cause of heart disease and does not cause the clogged arteries. Atherosclerosis has now been established as an inflammatory disease. Yes, it is the lesions in the arteries that develop in the process of atherosclerosis that do lead to heart attack and stroke. So the picture above is partly true, but it’s not cholesterol, that’s the part where we’ve all gone wrong.
Believe it or not, the process of atherosclerosis actually begins in childhood with streaks appearing in the blood vessels, that’s why age is an unmodifiable risk factor. As we age our risk goes up. But why does this happen and how?
Heart Disease Is Caused By Inflammation
As I said above, atherosclerosis is an inflammatory condition, there is no doubt about it. So far the studies suggest a ‘response to injury’ theory that leads to endothelial dysfunction as a primary cause. The endothelial cells form the endothelium. The endothelium is the thin layer that lines the interior surfaces of all blood and lymph vessels. So in plain talk, your arteries are lined by a thin layer called your endothelium. Here’s a picture that shows you where that is.
So let’s talk about this ‘response to injury’ and what happens as a result.
Response to injury
Something that can act like an injury could be the overconsumption of a nutrient, for example, excess salt. That’s just one nutrient, but as you can imagine, in the Western diet full of sugar, refined and processed products, bad commercial seed oils, and loads of other things, there could be a lot of injury occuring. YES, diet and nutrition are a predominant cause of this ‘response to injury’ theory.
But what happens is not cholesterol getting stuck in your arteries, what happens is changes in the artery wall because of this injury and the inflammatory response that occurs.
The process of inflammation in heart disease
In usual circumstances, the endothelium maintains a vasodilator, antithrombotic and anti-inflammatory state. But the injury to the endothelium (the lining of the arteries) increases adhesiveness of the artery wall, increases vascular permeability (meaning the wall is no longer solid), and changes the endothelium (the artery lining) from anticoagulant to pro-coagulant. This promotes active formation of molecules, cytokines and growth factors in the arteries and is an inflammatory response.
Once the inflammatory response ignites, vascular smooth muscle cells (that’s the cells in your arteries) migrate and proliferate to intermix with the inflamed area and create a lesion. So essentially cells in the artery walls can break up and start moving, the cells are changing, the lining of the artery can be permeated, they and that’s what is creating the lesions. The lesions are what clogs the arteries. Eventually this can lead to thickening of the artery walls (as the lesions grow). So if the inflammatory stimulus just keeps on going and keeps causing injury, this can result in the development of advanced, complicated lesions that lead to heart attack and stroke.
Yes the picture still looks similar but it’s not cholesterol, it’s injury that leads to inflammation, that then leads to lesions occuring.
If you want to understand more about the process of inflammation, I wrote about it over here recently and also recorded a podcast about it. So check those out to get a better understanding of how inflammation affects our body.
I hope you now understand what causes heart disease and no longer believe the common myth surrounding cholesterol. As for what we can do about it and busting some myths on cholesterol, I’ll be covering those too, so be sure to Click here to subscribe for updates newsletter.
Nutrition & Health Coach