Wednesday, November 10, 2010

Heart Disease: The Cholesterol Link - LDL Cholesterol

What is LDL Cholesterol? 
Cholesterol is a waxy substance that is made by your liver and found in the cell membranes and blood. You can also get it from the foods you eat. Low-density lipoprotein cholesterol, or LDL cholesterol for short, is called bad cholesterol because if you have too much of this form of cholesterol in your blood, it can lead to a heart attack or stroke.

Cholesterol also travels through your body as high-density lipoprotein cholesterol or HDL cholesterol. HDL cholesterol is called good cholesterol because it has a favorable effect on your health. An important function is to clear the LDL or bad cholesterol from your blood. This can help to lower your risk of a heart attack or stroke.

The Good News About Cholesterol
You hear so much about the harmful effect of high cholesterol that you probably never stop to think that this substance could be of any good.  That is where you would be mistaken. In fact, you actually need cholesterol for a number of important functions. For example, cholesterol is used to make vitamin D. It is also used for making hormones like estrogen and testosterone, and is an important part of the structure and function of nerves and the membrane of every cell.

The Bad News About LDL Cholesterol - Plaque
LDL cholesterol becomes dangerous when there is too much in your blood. That is because when the levels get too high, it could cause plaque to build up in your blood vessels. This in turn can cause the arteries to become narrow and interfere with normal blood flow to your heart. When this happens, your heart may not get enough oxygen. As a result, it has to work harder and can become damaged from lack of oxygen and the increased work it must perform.

Another serious danger of plaque is that it can break away from the arterial wall, form a blood clot and block the flow of blood to vital organs like the heart or brain. The end result could be a heart attack or a stroke.

Reducing Your Risk of Cardiovascular Disease
You can reduce your risk of a heart attack or stroke by keeping your LDL cholesterol low and your HDL high.

What Your Cholesterol Numbers Mean
Knowing your cholesterol numbers can help you determine if you are at risk for cholesterol-related cardiovascular disease. A simple blood test can be done to measure your LDL and HDL cholesterol levels. Make a special effort to know your numbers and what they mean. The following information may be helpful. (I will discuss ways to lower your LDL cholesterol and raise your HDL cholesterol in the next blog.)

Total cholesterol:
Less than 200 mg/dL is considered desirable
200 - 239 is borderline high
240 mg/dL and above is high

LDL cholesterol:
Less than 100 mg/dL is optimal
100 to 129 near optimal
130 - 159 mg/dL is borderline
160 - 189 mg/dL is high
190 mg/dL and above is very high

HDL cholesterol:
60 and above is high, which means it is protective
40 mg/dL and above for men and 60 and above for women is good
Below 40 is bad