LDL Cholesterol

The normal reference range for LDL Cholesterol is Targets are risk-based rather than a single normal range. Below 2.0 mmol/L is a common target for people at high cardiovascular risk; below 1.4 mmol/L for very high risk (established heart disease or diabetes with complications). For low-risk adults, below ~3.0 mmol/L is generally reasonable.. Reference ranges may vary between laboratories, so always consult your healthcare provider for interpretation.

LDL is a primary driver of atherosclerosis (plaque build up in arteries) and cardiovascular disease risk, making it a key target for heart disease prevention.

High LDL accelerates plaque build-up in the arteries. The most common causes are a diet high in saturated and trans fats, being overweight, and physical inactivity, but it is also strongly influenced by genetics — familial hypercholesterolaemia causes very high LDL from a young age and affects about 1 in 250 Australians. Secondary causes include hypothyroidism, poorly controlled diabetes, kidney disease (nephrotic syndrome), cholestatic liver disease and certain medications.

Low LDL is generally desirable and is the main goal of statin and other lipid-lowering therapy. Naturally low levels may occur with an overactive thyroid, malnutrition or malabsorption, severe liver disease, chronic illness, or rare inherited conditions. Very low LDL from these causes warrants looking at the underlying reason.

LDL is measured on a fasting lipid panel. Healthy adults are screened every 5 years from age 45 (from 35 for Aboriginal and Torres Strait Islander people). After starting or changing therapy, recheck at 6-12 weeks, then every 6-12 months once at target.