We hear a lot of talk about a number of different kinds of cholesterol: good, bad, HDL, LDL, VLDL, triglycerides, lipids and more. If you're not a medical professional, it's tough to keep it all straight.

In the following article, we' attempt to expand your knowledge of what low density lipopropteins or LDL cholesterol is - the type that's often called "bad" cholesterol - and the role it plays in overall cholesterol health.

First, let's have a quick refresher on exactly what cholesterol is and how it functions in your body.

Cholesterol is a waxy, fat-like substance that circulates in the blood. The body manufactures cholesterol naturally, predominantly in the liver. We get more from the food we eat. But because cholesterol is incapable of traveling through the bloodstream alone, it must attach itself to a protein. This combination is called a "lipoprotein."

LDL is an abbreviation for "low density lipoprotein." This is the so-called "bad" cholesterol you hear about. One of our cardiologist acquaintances says it's easy to remember if you think of low density lipoproteins as "low down and lousy." LDL tends to stick to the walls of your arteries, building up in the form of a substance doctors call plaque. This is the material that causes hardening of the arteries and leads to heart disease or a stroke.

HDL stands for "high density lipoprotein." HDL is good not only because it does not create arterial plaque, but also because it attaches to LDL and escorts it to the liver, which removes it from the body. The more HDL you have, the less LDL you are likely to have, and the lower your risk of heart disease will be.

A lot of the LDL cholesterol in our diet comes from fats in the foods we eat: especially two types of fats. These are known as saturated fats and trans fats. You find these unhealthy fats in meat (especially the red variety), certain oils (like those used for french fries in fast food restaurants), prepackaged and processed foods, and baked goods like donuts, cake, muffins, etc.

By avoiding trans fats and saturated fats, and eating heart-friendly foods such as grains, fruits, vegetables, and healthier meats like poultry and fish, you can lower your LDL and increase your HDL..

The simple abbreviations LDL and HDL can be confusing if you're not used to medical terminology, and it may be tough to remember which is and which is bad. Just try to remember that that LDL stands for low density, while HDL is high density, and in this case, low is bad and high is good. Or as our cardiologist acquaintance says, "Low has got to go..."

By maintaining a healthy ratio between your HDL and your LDL, you reduce your risk of cardiovascular "events" like heart attacks and stroke. Exercise is also important. Research has proven that getting your heart rate up with vigorous physical activity helps your HDL cholesterol clean the LDL out of your system.

When you have your cholesterol tested, your doctor will probably explain your numbers in terms of total cholesterol, HDL and LDL levels. Ideal HDL is 60 mg/dL or higher. Your ideal LDL level should be 100 mg/dL or lower. Your doctor may also give you the relationship between LDL and HDL as a ratio. The lower the ratio of LDL over HDL, the better.

It's important to measure your cholesterol often. Research in recent years has shown that high cholesterol is becoming a serious health problem in younger and younger age groups. Doctors now say even teenagers and 20-somethings should have cholesterol and blood pressure checked. This is because most kids these days eat a fatty, cholesterol-rich diet and don't get much exercise. Therefore, hypertension (high blood pressure) and high cholesterol are becoming health threats for younger people much more so than they were for previous generations.