Does this test have other names?
Low-density lipoprotein-cholesterol, LDL-C
What is this test?
This test measures the amount of low-density lipoprotein-cholesterol (LDL-C) in your
LDL cholesterol is often called "bad" cholesterol because it causes plaque to build
up inside your arteries and leads to heart disease.
Cholesterol screening is advised every 4 to 6 years for adults ages 20 and older who
are at low risk for heart disease. You may need to have your blood tested more often
if you have risk factors for heart disease or stroke. Talk with your healthcare provider.
LDL cholesterol is one of a group of lipoproteins that can indicate heart disease,
so this test is used to help diagnose it.
Lowering LDL-C levels can help prevent heart disease.
Why do I need this test?
You may need this test as part of a routine exam to check for high cholesterol.
You may also have this test if you already have heart disease caused by high cholesterol.
The test can help your healthcare provider find out how well your treatment is working.
What other tests might I have along with this test?
Your healthcare provider may also order other blood tests to measure the levels of
various fats in your blood. These include:
What do my test results mean?
Test results may vary depending on your age, gender, health history, the method used
for the test, and other things. Your test results may not mean you have a problem.
Ask your healthcare provider what your test results mean for you.
Results are given in milligrams per deciliter (mg/dL). The normal range of LDL-C is
50 to 100 mg/dL. Depending on all your risk factors, in general:
Less than 100 is optimal
100 to 129 mg/dL is near or just above optimal
130 to 159 mg/dL is borderline high
160 to 189 mg/dL is high
190 mg/dL and over is very high
The optimal level of LDL has changed over time and depends on all your risk factors.
Generally, a LDL cholesterol level of 100 mg/dL may be a good goal. A level below
70 mg/dL is considered best for people who have diabetes or heart disease risk factors.
High cholesterol is only one of the big risk factors for heart disease and stroke.
Other things that can increase your risk include:
To help find your overall risk, your provider may use a risk calculator. It takes
into account your cholesterol level and other risk factors. Ask your healthcare provider
about your 10-year risk if you are older than age 40 or your lifetime risk if you
are age 20 to 39. Depending on all your risk factors, your healthcare provider will
talk with you about your cholesterol results and what is important for overall health.
It's possible to have extremely low levels of LDL-C, but this is rare. This condition
is usually a sign of a problem processing vitamins A, D, E, and K.
If your levels of LDL-C are very high, the condition is called dyslipidemia. High
levels may mean that you have an imbalance in your diet. But the condition is often
genetic and known as familial hypercholesterolemia.
If your cholesterol level is higher than normal, your healthcare provider will tell
you how to lower your level. Changing your lifestyle habits and taking medicines to
reduce LDL levels may help you lower your risk for heart disease. It can also help
you manage the condition if you already have it.
How is this test done?
The test is done with a blood sample. A needle is used to draw blood from a vein in
your arm or hand.
Does this test pose any risks?
Having a blood test with a needle carries some risks. These include bleeding, infection,
bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may
feel a slight sting or pain. Afterward, the site may be sore.
What might affect my test results?
Smoking cigarettes can increase LDL-C levels. Stress, certain minor ailments, and
some medicines can also affect your results.
How do I get ready for this test?
Testing of your cholesterol level does not need fasting in most cases. But your healthcare
provider may ask you to not eat or drink anything but water for a certain time before
having the test. Be sure your healthcare provider knows about all medicines, herbs,
vitamins, and supplements you are taking. This includes medicines that don't need
a prescription and any illegal drugs you may use.