ApoB
A direct count of the cholesterol-carrying particles that can lodge in artery walls.
What is it
Apolipoprotein B is a protein attached to every cholesterol-carrying particle that can contribute to plaque — including LDL, VLDL, IDL, and Lp(a). Each particle carries one ApoB tag, so measuring ApoB gives a direct count of those particles in circulation.
A standard cholesterol panel measures how much cholesterol is being carried. ApoB measures how many vehicles are doing the carrying.
Why it's measured
ApoB has been linked to cardiovascular risk in a growing body of research. It is not routinely included in standard cholesterol panels and is most often ordered as part of advanced lipid testing or by a cardiologist.
Because a single number reflects every plaque-forming particle, ApoB has become a focus of cardiometabolic research and is increasingly discussed in clinical guidelines on lipid management.
Reference range
Standard laboratory reference
< 90 mg/dL
Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.
What results may indicate
Elevated
Has been associated with a higher number of cholesterol-carrying particles in circulation, which research has linked to increased cardiovascular risk.
Lower
Is generally considered favorable in published research on cardiovascular health.
These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.
When it's measured
ApoB is often included in advanced or comprehensive lipid testing. It is not part of a standard cholesterol panel and most people have never had it measured. Frequency of testing should be determined with your physician based on your health profile and risk factors.
Related markers
Common questions
Apolipoprotein B is a protein attached to every cholesterol-carrying particle that can contribute to plaque \u2014 including LDL, VLDL, IDL, and Lp(a). Each particle carries one ApoB tag, so measuring ApoB gives a direct count of those particles in circulation.A standard cholesterol panel measures how much cholesterol is being carried. ApoB measures how many vehicles are doing the carrying.
It's one of the markers used to build a fuller picture of your health. On its own it tells you very little, so it's most informative when reviewed alongside related markers.
It's measured from a standard blood draw at Quest or LabCorp. Apolipoprotein B (ApoB) is one of the markers included in the OPTML Apex Panel, where your results are read across systems and reviewed by a U.S.-licensed physician.
Reference ranges vary by laboratory, and a single value rarely tells the whole story. Review your result with a physician in the context of your other markers, symptoms, and history.
Apolipoprotein B (ApoB) is one signal among many. Answer a few quick questions and we’ll point you to the panel that fits.
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Explore the Apex Panel →This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.