A cholesterol test measures the amount of cholesterol and triglycerides in your blood. Knowing your cholesterol levels helps your doctor to assess your overall heart health.
What is a cholesterol test?
The only way to find out if your cholesterol is high is to have a blood test called a cholesterol test (also called lipid profile). The cholesterol test measures the following:
- high-density lipoprotein (HDL) cholesterol
- low-density lipoprotein (LDL) cholesterol
- total cholesterol
- total cholesterol/HDL ratio.
These make up your blood lipid profile. Lipids are just another name for the fatty substances in your body and bloodstream.
Why would I need a cholesterol test?
Cholesterol tests are done routinely as part of a heart health check.
Knowing your cholesterol levels helps your doctor to assess your overall heart health. When your cholesterol is too high it can build up as plaque in your arteries. If the plaque gets too big, or breaks off, it can cause a heart attack and stroke. This risk also increases when your triglycerides are too high.
Your doctor will use the results of your blood test and your other heart attack risk factors to decide whether you need medication to lower your cholesterol or triglyceride levels. Read more about heart health check.
How do I prepare for a cholesterol test?
Generally, you won't need to do anything before having this test. It can be done at any time of the day and usually fasting before the test is not required. If your triglycerides are high then your doctor may recommend fasting before repeating the test, because triglycerides may vary depending how recently you've consumed fat in your diet.
What does the test involve?
Your doctor may ask you to have the cholesterol test at the nearest community diagnostic laboratory, or the practice nurse may be able to take the blood sample.
A cholesterol test is a blood test which means a small amount of blood is taken by placing needle placed in a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight for a few seconds. You may feel nothing at all from the needle, or you may feel a small brief sting or pinch. The blood sample is collected in a tube, which is sent to the laboratory for analysis. Read more about blood tests.
Cholesterol testing in pharmacies
Some New Zealand pharmacies also offer a cholesterol testing service, using a portable testing device. This is a finger-prick test that measures the same things as the blood tests, but is slightly less accurate. If the reading is high, your pharmacist will send you to your GP for a follow-up appointment.
Note: There is a charge for this service.
What do my cholesterol test results mean?
Your doctor will discuss your test results with you. The results are not interpreted on their own and are not used to diagnose a disease. Instead, they provide information on your overall health and your risk of heart attack and stroke. Sometimes high cholesterol levels can be an early warning to make lifestyle changes to lower your risk of cardiovascular disease.
Your doctor will use other cardiovascular disease risk factors such as your age, sex, blood pressure and whether you smoke or have diabetes when deciding whether treatment is needed. Read more about what do my cholesterol results mean.