How often should I have my cholesterol levels checked?
The National Cholesterol Education Program of the National Heart, Lung, and Blood Institute, National Institutes of Health recommend that everyone above the age of 20 should have their cholesterol measured at least once every 5 years.1 If your levels are high or you have risk factors for heart disease, you will be retested more often. The best test to have is the fasting lipid (or lipoprotein) profile. There is evidence that women are less likely than men to be tested and treated for high cholesterol.29-31
What does a cholesterol test measure?
There are two types of cholesterol test. The preferred test is a lipid (or lipoprotein) profile. This is a fasting blood test, meaning you do not eat for 9 to 12 hours before the test. It measures:
- total blood cholesterol
- LDL (bad) cholesterol
- HDL (good) cholesterol
If you can't have a lipid profile done, you can have your total cholesterol measured without having to fast.
How do I prepare for a cholesterol test?
If you are just having a total cholesterol test, then there is no special preparation. For a fasting lipid profile (the better test) you will not be allowed to eat anything for 9 to 12 hours before the test. You should follow your healthcare provider's restrictions on diet, exercise, and medication use prior to the test.
You should also tell your healthcare provider about all prescription and over-the-counter medications you are taking, because some of these may affect the accuracy of the test. If you have diabetes, you should discuss dietary concerns for the day of the test with your healthcare provider in order to moderate your blood sugar levels.
What does a cholesterol test entail?
For a fasting lipid profile and most cholesterol tests, a blood sample is taken from a vein in your arm. Some total cholesterol tests use only a finger prick of blood. The test takes less than a minute and the results should be available in a day or two.
Does a cholesterol test have any limitations?
Yes. Cholesterol should not be measured when you are sick or if you just had an accident or surgery, because these events can temporarily lower your blood cholesterol. Cholesterol levels are higher during pregnancy; pregnant women should wait until 6 weeks after the baby is born before having a cholesterol test. Certain medications including anabolic steroids, some high blood pressure medicines, hormones, and birth control pills can affect cholesterol levels.
If your test results are high, your healthcare provider should check if the high cholesterol is caused by medications you are taking, liver problems, or an underactive thyroid gland.