Apolipoprotein B

What is Apolipoprotein B?

Apolipoprotein B is the primary protein component found in LDL (low-density lipoprotein) particles. Unlike LDL cholesterol, which measures the cholesterol content within these particles, ApoB counts the actual number of potentially harmful particles in your blood. Each LDL particle contains exactly one ApoB protein, making it a direct measure of particle count.

Why is it Tested?

Doctors order ApoB to better assess cardiovascular risk, especially when standard lipid panels show conflicting results. Research suggests ApoB may be a superior predictor of heart disease risk compared to LDL cholesterol alone, particularly in people with diabetes, metabolic syndrome, or high triglycerides where LDL particles tend to be smaller and denser.

Normal Ranges

What do Abnormal Results Mean?

Abnormal results are not a diagnosis. Always discuss your results with a qualified healthcare provider before making any medical decisions.

Low ApoB

Lower ApoB levels indicate fewer atherogenic particles and are associated with reduced cardiovascular risk. This is generally considered favorable unless levels are extremely low due to rare genetic conditions affecting lipoprotein production.

High ApoB

Elevated ApoB suggests increased numbers of potentially harmful particles and may indicate:

• Increased cardiovascular disease risk
• Familial hypercholesterolemia
• Metabolic syndrome
• Insulin resistance
• Need for lipid-lowering therapy

How to Track Over Time

Tracking ApoB trends helps monitor cardiovascular risk management and response to lifestyle changes or medications. Unlike LDL cholesterol, ApoB levels aren’t significantly affected by recent meals, making them useful for assessing long-term patterns in particle burden and treatment effectiveness.