To Your Health January, 2009 (Vol. 03, Issue 01)

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A Matter of the Heart: What You Need to Know About Cholesterol

By James P. Meschino, DC, MS

Cardiovascular disease is the number-one killer in our society, claiming the lives of one of every two men and one of every three women. High cholesterol is a cardinal risk factor for heart attack, stroke and other vascular diseases. Do you understand what cholesterol is, how it functions in the body and what you can do naturally to keep your cholesterol levels within a healthy range? Here's a quick introduction.

What Is Cholesterol?

Cholesterol is a fatty, waxy material that is found in high-fat meat and dairy products, as well as egg yolks, organ meats and shellfish. Our bodies make additional cholesterol in the liver when we eat foods that contain a lot of saturated fat such as beef, pork, lamb, high-fat dairy products, chocolate (made with cocoa butter), and possibly coconut and palm oil. Eating trans fats (hydrogenated fats) found in many fried foods, cookies, pastries, muffins and shortenings also increases the body's cholesterol production.

Most of the cholesterol you eat is absorbed and transported to the liver. Once in the liver, cholesterol, including the cholesterol your liver makes when you eat foods high in saturated fat and/or trans fats, is transported out of the liver in a carrier vehicle known as VLDL (very low-density lipoprotein). The VLDL looks a bit like an egg. Its outer shell is made out of protein and the inside of the shell has cholesterol, where the white of the egg would normally reside. In this model, the yolk represents triglycerides.  Triglycerides are the are the chemical form in which most fat exists in food as well as in the body.

As the VLDL circulates through the bloodstream, the triglycerides are taken up by your fat cells (and your fat cells in turn get larger) and your muscles. Fat is the primary fuel that muscles burn when you are at rest and during light to moderate activity. Thus, the more muscle mass you have, the faster you burn fat, even when sitting in a chair.  Once the triglycerides are removed from the VLDL, the remnant particle is known as the LDL (low-density lipoprotein) cholesterol, which is the bad cholesterol that promotes heart attack and stroke.

How Does LDL CholesterolPromote Heart Attack and Stroke?

Although various body tissues remove LDL ("bad") cholesterol from the bloodstream and use the cholesterol to make cell membranes, bile acids, vitamin D and various hormones (e.g. estrogen, progesterone, cortisone, testosterone), once the tissues have acquired all the cholesterol they need, they stop extracting LDL cholesterol from the bloodstream. Any extra LDL cholesterol continues to circulate in your arteries.

This is where the trouble begins, as LDL cholesterol tends to stick to the walls of the artery, causing progressive narrowing of these important blood vessels. It's a bit more complex than this, but the bottom line is that excess LDL cholesterol causes narrowing of your arteries. Once 85 percent of the artery is blocked with LDL cholesterol, plaque symptoms start to occur, such as angina and transient ischemic attacks (resembling mini-strokes).

In up to 40 percent of cases, the first symptom is a sudden-death heart attack. Waiting for symptoms to occur is not a good idea. A good idea is to keep your LDL cholesterol level within the safe and desirable zone, which is under 2.5 mmol/L (96 mg/dL).  If you already have had a heart attack, stroke or heart operation, or have diabetes or kidney disease (including kidney transplant), then you should aim for an LDL cholesterol level at or below 2.0 mmol/L (77 mg/dL).