Description of the test
Cholesterol testing analyzes the level of cholesterol (a fatty substance) in the blood. A technician in a hospital or clinic takes a sample of blood using a needle. The test takes less than 10 minutes to complete.
Naturally found in the body, cholesterol has many important roles. Cells use it to make protective outer coverings and hormones. Cholesterol can come from two sources: the food you eat, and your own body, which produces some cholesterol.
A patient having blood collected for a cholesterol test
How often should this test be performed?
Your age, health, and risk of having cardiovascular disease will determine how frequently your need this test. Usually young, healthy people are only tested occasionally. As you get older you may need to have it checked annually. More frequent testing may be recommended if you:
Why is this test performed?
A high level of LDL (bad) cholesterol in the blood is a risk factor for certain serious conditions. Heart attacks and stroke are two conditions associated with high LDL cholesterol levels. Higher levels of HDL (good cholesterol) can help protect against heart disease and stroke. Testing for LDL cholesterol levels and total cholesterol (both good and bad cholesterol) is important because your doctor can:
- determine your risk for serious conditions
- treat high LDL cholesterol through a combination of diet, exercise, and medication
- monitor the effectiveness of medication you are taking to lower your cholesterol levels
Are there any risks and precautions I should know about?
Although blood tests are very safe, you may experience:
- slight bruising or tenderness where the needle enters the vein
- infection (if the area was not properly sterilized before the sample was taken)
- excess bleeding from the area that was punctured
People with bleeding disorders or anyone taking medication that reduces the ability of the blood to clot (e.g., warfarin, aspirin, or other anticoagulants) should tell the technician before the blood samples are taken. These conditions and medications may require special attention at the time of testing.
Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any medication allergies and medical conditions that you may have. Ask your doctor or pharmacist whether you need to stop taking any of your medications before the procedure.