Cholesterol is a waxy, fat-like substance that the body needs for building cell membranes, producing hormones, and making bile acids that help digest fat. Most cholesterol is produced by the liver, with a smaller amount coming from dietary sources. Problems arise when there is too much cholesterol circulating in the blood, particularly certain types.
This test measures your total cholesterol, which is the combined amount of all cholesterol-carrying lipoproteins in your blood: HDL (high-density lipoprotein), LDL (low-density lipoprotein), and a smaller contribution from VLDL and other particles. It gives a broad, single-number snapshot of where your cholesterol sits.
Total cholesterol below 5.5 mmol/L is the general target for adults in Australia. Levels between 5.5 and 6.5 mmol/L are considered borderline, and above 6.5 mmol/L is considered high. However, total cholesterol alone does not tell you which types of cholesterol are contributing to the number. A result driven by high HDL (the protective type) has a very different risk profile from one driven by high LDL.
For that reason, total cholesterol works best as a screening tool or a quick tracking measure. If your result comes back elevated, a full lipid panel (total cholesterol, HDL, LDL, and triglycerides) gives the breakdown needed to properly assess cardiovascular risk.
Cholesterol levels are influenced by genetics, diet, body weight, physical activity, and age. Some people have familial hypercholesterolaemia, a genetic condition causing elevated cholesterol regardless of lifestyle. If you have a family history of early heart disease or high cholesterol, testing is particularly relevant.
This test provides a broad indication of your cholesterol level. It's suited to people who want a quick initial check, or who are tracking total cholesterol over time. For a complete cardiovascular risk assessment, a full lipid panel (including HDL, LDL, and triglycerides) gives more actionable information.
