Total Cholesterol

The normal reference range for Total Cholesterol is Below 5.5 mmol/L is the general Australian target, dropping to below 4.0 mmol/L for people at high cardiovascular risk. Total cholesterol on its own is a blunt measure — it includes protective HDL — so it is always interpreted with the HDL, LDL and triglyceride breakdown.. Reference ranges may vary between laboratories, so always consult your healthcare provider for interpretation.

Elevated total cholesterol is a risk factor for atherosclerosis and heart disease.

High total cholesterol can come from raised LDL, raised HDL, or both, which is why the breakdown matters. Common drivers of harmful elevation are a diet high in saturated and trans fats, being overweight, physical inactivity and genetics (familial hypercholesterolaemia). Secondary causes include hypothyroidism, poorly controlled diabetes, kidney disease, cholestatic liver disease and pregnancy.

Low total cholesterol is usually not a problem and often reflects effective lipid-lowering treatment. When unexpectedly low, it can point to an overactive thyroid, malnutrition or malabsorption, severe liver disease, or chronic inflammatory illness — situations where the underlying cause is what needs attention.

Total cholesterol is part of a fasting lipid panel. Healthy adults are screened every 5 years from age 45 (from 35 for Aboriginal and Torres Strait Islander people, and earlier with risk factors). On treatment, recheck 6-12 weeks after changes, then every 6-12 months.