LDL cholesterol (LDL-C)

The cholesterol most likely to build up in your artery walls — often called the “bad” cholesterol.

What it measures

The amount of cholesterol carried in low-density lipoprotein particles in your blood.

Why it matters

Over a lifetime, higher LDL cholesterol drives the fatty plaques behind most heart attacks and strokes. It is one of the few numbers where lower, for longer, is reliably better — and it is highly modifiable.

Healthy target

< 2.6 mmol/L

How to read your value

Standard lab cut-offs are set for average risk; a longevity-oriented target sits below them. One high reading isn’t a diagnosis — trend and your overall risk (blood pressure, smoking, family history) matter more than a single value.

What can affect it

• Saturated fat intake and diet pattern
• Genetics (some people are high despite a good diet — familial hypercholesterolaemia)
• Body weight and physical activity
• Thyroid function and some medications
• Statins and other lipid-lowering drugs lower it substantially

Does the target differ by age or sex?

Same target for men and women — the “lower is better” direction holds across adult life. Your absolute risk rises with age, so a clinician decides when to treat. Pregnancy and childhood have their own ranges.

When to talk to a clinician

Discuss treatment if LDL stays high despite lifestyle changes, if it is very high (possible inherited cause), or if you already have cardiovascular disease or diabetes.