The question about whether cholesterol is a friend, or a foe, comes from Health Canada, of all places. What could they mean? Don’t we all know cholesterol is bad for us? That too much can lead to clogged arteries, heart attack and stroke? Well, yes. And, of course, no.

As with most substances created by our bodies, there are both good and bad sides to the answer. Problems arise when our bodies create too much, or too little, of a particular substance. Such is the case with cholesterol. This is further complicated by the presence of both “good” and “bad” types of cholesterol. More on that later.

The number one killer in North America are heart attacks and strokes, both closely associated with clogged arteries. The proper term for this is atherosclerosis, which translates literally to “hardening of the arteries.” Already the picture is becoming clearer, isn’t it? If the clogged artery supplies blood to your heart, you have a heart attack. If it feeds the brain, then you have a stroke. Pretty simple, isn’t it?

For 80 years we have known about the connection between fatty substances in our blood and the clogging that occurs as atherosclerosis. The main components of the fatty substances are cholesterol and triglycerides. Cholesterol is a waxy substance produced naturally by the body to be used in cell membranes, some hormones and other tissue. And the body can manufacture all it needs. Triglycerides are used by muscles and fatty tissue to store energy.

Moving these two substances around the body is the job of lipoproteins, not unlike moving around little bubbles of grease with a protein coating. (The imagery should help you understand atherosclerosis already.) These lipoproteins come in two flavours, LDL and HDL.

Low Density Lipoproteins are also referred to as “bad” cholesterol. Their job is to distribute cholesterol throughout the body. You might liken them to “grease spillers.” High Density Lipoproteins, on the other hand, behave more like a good paper towel after a barbeque: they absorb and rid the body of cholesterol via the bloodstream.

Some cholesterol is needed for bodies to function, but too much of the “bad” (LDL) and your blood vessels start to clog up. But what is too much? In fact, the total quantity of cholesterol is not really the issue. A more accurate measure is the level of good cholesterol (HDL) as a proportion of total cholesterol. The situation of too much bad/LDL and not enough good/HDL mostly arises in people where the normal processing of fats has been disturbed by outside factors. These can include: medications such as for blood pressure, birth control and steroids; diseases like diabetes, kidney disease or under-active thyroid gland; or from weight gain.

Back to Health Canada: Cholesterol is our friend because it helps form or repair cell membranes, some hormones, and other tissues. It is also a foe because if you have too much, you can develop hardening of the arteries and run the risk of heart attacks or stroke.

You may feel just fine, even if your cholesterol levels are too high (just to confirm, that means too much HDL, right?). Why worry, then? Controlling cholesterol is all about preventative maintenance… just like an oil change on your vehicle. It may run apparently problem-free for a long time, until the engine finally seizes up… and you die!

Our next article will be about eating heart-healthy. Your homework in the meantime is to check your “Cholesterol & Heart Disease I.Q.” at the National Heart, Lung and Blood Institute website at <ww.nhlbi.nih.gov/health/public/heart/chol/chol_iq.htm >. You should do well now that you have read this.

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Call-out:
“Controlling cholesterol is all about preventative maintenance… just like an oil change on your vehicle. It may run apparently problem-free for a long time, until the engine finally seizes up… and you die!”