Health Measurements: Blood Cholesterol

What is it?

A fat-like substance that is made by the body and also found naturally in animal products such as meat, fish, poultry, eggs, and cheese. Blood cholesterol is often measured in 3 ways:  Total (all forms are included), HDL and LDL. The cholesterol you eat has little to do with the cholesterol in your blood.  Much more important are other aspects of diet such as saturated fats and dietary fiber.

Why is it included?

If there is too much cholesterol in the blood, excess can build up in artery walls directly contributing to heart disease. High cholesterol is one of several factors like blood pressure and diabetes that increase the likelihood of heart disease.

Good vs. Bad Cholesterol

LDL cholesterol can build up inside your blood vessels, leading to narrowing and hardening of your arteries—the blood vessels that carry blood from the heart to the rest of the body. That is why we call it “lousy” (plus it’s easy to remember that LDL and lousy both begin with an “L”). Arteries can then become blocked. Therefore, high levels of LDL cholesterol raise your risk of getting heart disease.

HDL is the “healthy” cholesterol found in the blood stream. HDL cholesterol removes deposits from inside your blood vessels and takes them to the liver for removal. Low levels of HDL cholesterol increase your risk for heart disease.
              
Triglycerides are also important to consider when you are talking about cholesterol. Triglycerides are fats that circulate in the bloodstream and are the form that fat is stored as in your body. High levels often appear with other well-known risk factors for heart disease, such as high blood cholesterol and diabetes. Elevated triglycerides are linked to a greater risk of heart disease in women (as compared to men). A high triglyceride level combined with low HDL cholesterol or high LDL cholesterol seems to speed the buildup of fatty deposits in artery walls and the chance of a heart attack and stroke.

How is it measured?

A simple blood test, called a fasting lipoprotein profile, checks for high fats in the blood. You may be asked to fast overnight before the test, hence its name. A fasting lipoprotein profile measures total cholesterol, LDL (Lousy) cholesterol, HDL (Healthy) cholesterol, and triglycerides in your blood.  A cholesterol test can be done without fasting, but then only the levels of total cholesterol and HDL (Healthy) cholesterol can be measured. 

Ranges

Total Cholesterol/Lipid profile:
Normal Total Cholesterol = < 200
Normal LDL (Lousy) Cholesterol = <100
Normal HDL (Healthy) Cholesterol = > 40
Normal Triglycerides = < 150

Additional Resources

Cholesterol FAQs
Centers for Disease Control and Prevention (CDC)
Your Guide to Lowering Your Cholesterol with TLC
American Heart Association: Information on Cholesterol