Apolipoprotein B
The protein found on LDL and other artery-clogging particles. Because each such particle carries one ApoB, it is a strong marker of cardiovascular risk.
Typical reference range
| Range | Unit |
|---|---|
| 0–1 | g/l |
What Apolipoprotein B measures
Apolipoprotein B (ApoB) is a protein carried on the atherogenic, or artery-clogging, cholesterol particles, mainly LDL along with related lipoproteins. Because there is roughly one ApoB molecule per particle, measuring it effectively counts the number of these particles circulating in the blood rather than the amount of cholesterol they carry.
ApoB is increasingly used as a refinement of, or a complement to, standard LDL cholesterol when estimating cardiovascular risk. Two people can share the same LDL cholesterol value yet carry very different particle numbers, and ApoB helps capture that difference. It is best read alongside a standard lipid panel and your broader risk picture, and interpreted with a clinician rather than on its own.
What a high Apolipoprotein B can mean
A high ApoB reflects a greater number of atherogenic particles in the blood, and this higher particle count is associated with higher cardiovascular risk. In many cases it moves together with elevated LDL cholesterol or triglycerides.
ApoB can be raised in the same settings that raise LDL and triglycerides, including dietary patterns, genetic conditions such as familial hypercholesterolemia, and insulin resistance or metabolic syndrome. The same lifestyle levers that tend to lower LDL, such as dietary changes and physical activity, generally tend to lower ApoB as well.
- Consider it a refinement of your risk estimate, not a diagnosis on its own.
- Interpret it together with your full lipid panel and personal risk factors.
- Any decisions about medication belong with a clinician who knows your history.
What a low Apolipoprotein B can mean
A low ApoB generally reflects a smaller number of atherogenic particles, which is usually considered favorable for cardiovascular risk. Fewer of these particles tends to align with a lower estimated burden on the arteries.
A low value can also accompany very low LDL cholesterol arising from genetics or from lipid-lowering treatment. On its own it is reassuring rather than a diagnosis, and it is most meaningful when read within the whole lipid and cardiovascular risk picture.
- Consider it alongside your full lipid panel and other risk factors.
- A very low result driven by treatment is typically an expected effect, not a concern.
- Discuss what your number means for you with a clinician who knows your history.
Track your Apolipoprotein B over time in Quanome — it reads your lab reports (PDF or photo) on your device, charts each marker against its range, and an AI coach explains what your trends mean alongside your Apple Health and DNA.