What is LDL cholesterol?
Cholesterol doesn't dissolve in water, so it travels through the blood packaged with proteins as lipoproteins. LDL carries cholesterol made in the liver out to the body, while HDL brings excess cholesterol back to the liver. Each LDL particle contains one apolipoprotein B, so the apoB level reflects the number of particles that can cause atherosclerosis.
Why is LDL called a cause of heart disease?
When blood LDL is high, particles slip into the artery wall and become oxidized; immune cells called macrophages engulf them and pile up, forming atherosclerotic plaque. If a plaque ruptures, a clot can form and trigger a heart attack or stroke. Because people with genetically low LDL for life have less heart disease, and many different LDL-lowering drugs reduce risk by similar amounts, experts regard LDL as a cause of atherosclerosis (Ference et al., 2017).
Levels and targets
Your LDL target depends on your risk. Very high-risk people who've had a heart attack or stroke aim low—below 55–70 mg/dL—while lower-risk people start with lifestyle changes. A 2010 meta-analysis by the CTT Collaboration found that every 1 mmol/L drop in LDL cut major vascular events by about 22%, with a similar proportional benefit even in people whose LDL started low. Risk climbs further with metabolic syndrome (belly fat, blood pressure and blood sugar problems together) or high blood pressure.
How to lower it
- Diet: cut saturated and trans fats, and add soluble fiber from oats, barley, beans and psyllium.
- Medication: statins are first-line; ezetimibe or PCSK9 inhibitors can be added if needed. Muscle aches blamed on statins are often a nocebo effect.
- Lifestyle: weight management, exercise and not smoking all help.
This article is general health information and is not a substitute for diagnosis or treatment. If symptoms persist, see a doctor.
FAQ
- What is a normal LDL level?
- For people without heart disease, under 100 mg/dL is generally considered optimal, but your personal target depends on your overall cardiovascular risk—ask your clinician.
Sources reviewed: 2026-10-25
References
- Cholesterol Treatment Trialists' (CTT) Collaboration. (2010). Efficacy and safety of more intensive lowering of LDL cholesterol. Lancet, 376(9753), 1670–1681.
- Ference, B. A., et al. (2017). Low-density lipoproteins cause atherosclerotic cardiovascular disease. European Heart Journal, 38(32), 2459–2472.
- Mach, F., et al. (2020). 2019 ESC/EAS Guidelines for the management of dyslipidaemias. European Heart Journal, 41(1), 111–188.