What is high cholesterol?

Cholesterol is a type of fat called a lipid. The body uses it for many things, such as making new cells. Your liver makes the cholesterol that your body needs. You also get cholesterol from the foods you eat.

Your body needs some cholesterol. But if you have too much, it starts to build up in your arteries. (Arteries are the blood vessels that carry blood away from the heart.) This is called hardening of the arteries, or atherosclerosis. It is usually a slow process that gets worse as you get older.

To understand what happens, think about how a clog forms in the pipe under a kitchen sink. Like the buildup of grease in the pipe, the buildup of cholesterol narrows your arteries and makes it harder for blood to flow through them. It reduces the amount of blood that gets to your body tissues, including your heart. This can lead to serious problems, including heart attack and stroke.

To find out how you are doing, compare your total cholesterol number to the following:

• Best is less than 200.
• Borderline-high is 200 to 239. Even borderline-high cholesterol makes you more likely to have a heart attack.
• High is 240 or above.

What are the symptoms?

High cholesterol doesn't make you feel sick. But if cholesterol builds up in your arteries, it can block blood flow to your heart or brain and cause a heart attack or stroke.

By the time you find out you have it, it may already be clogging your arteries. So it is very important to start treatment even though you may feel fine.

What are the different kinds of cholesterol?

Cholesterol travels through the blood attached to a protein. This package of cholesterol (a lipid) and protein is called a lipoprotein. Lipoproteins are either high-density or low-density, based on how much protein and fat they have.

• Low-density lipoproteins (LDL) are the "bad" cholesterol. LDL is mostly fat with only a small amount of protein. It can clog your arteries. If you have high cholesterol, your doctor will want you to lower your LDL.
• High-density lipoproteins (HDL) are the "good" cholesterol. HDL is more protein than fat. It helps clear the bad cholesterol from your blood so it does not clog your arteries. A high level of HDL can protect you from a heart attack.
• Triglycerides are another type of fat in the blood that can affect your health. If you have high triglycerides and high LDL, your chances of having a heart attack are higher.

It may help to think of HDL as the "Healthy" cholesterol and LDL as the "Lousy" cholesterol. Or you could remember that HDL should be High and LDL should be Low.