What is being tested?

The lipid profile includes total cholesterol, HDL-cholesterol (often called good cholesterol), LDL-cholesterol (often called bad cholesterol), and triglycerides.

Lipids and cholesterol are fat-like substances in the blood and some are necessary for good health. However, if you have a high level of LDL-cholesterol and triglycerides, then you have an increased risk of heart disease.

Why would I need this test?

You might need this test if your doctor wants to assess your risk of developing heart disease. It is usually recommended for people who are over 45 or who have high blood pressure or diabetes.

If you already have heart disease, or have problems with your cholesterol and triglycerides, then you will probably have these tests regularly to monitor the levels of these substances in your blood. If your levels of cholesterol and lipids go down, then your risk of having a heart attack goes down.

How to prepare for this test

You will need to fast (not have any food and only drink water) for between nine and 12 hours before having this test. Most people have the test in the morning so it doesn't interfere with their day and their meals. Talk to your doctor about any medications you take.

Understanding your results

While the levels of total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides are important, they must also be considered along with your specific risk factors for heart disease such as your age or blood pressure.

There are specific guidelines for target cholesterol levels in different people – talk to your doctor about this.

If your HDL levels are low and your LDL levels are high, your doctor will likely talk with you about how to change these and reduce your risk of heart disease. These might include:

• quitting if you smoke
• keeping your weight in a healthy range.
• limiting your alcohol and salt intake.
• aiming for at least 30 minutes of exercise on most days.

Your doctor might suggest medication to help keep your cholesterol in the healthy range. If you are on such medication, you might need regular cholesterol tests to check that they are working well and that you are taking the right dose.

More information

See Lab Tests Online for more information about testing cholesterol and lipids.

About blood testing

Visit our ‘Guide to blood testing’ to learn more about blood tests in general with information such as:

• what to consider before having the test
• what happens during a blood test
• results accuracy
• blood tests cost.