Apolipoprotein B

Measured in mg/dL

A count of the cholesterol-carrying particles most linked to artery buildup — one particle, one apoB — rather than the cholesterol inside them.

What it is

Apolipoprotein B (apoB) is a protein that sits on the surface of the lipoprotein particles associated with artery buildup, with roughly one copy per particle — so measuring apoB is effectively a count of those particles, whereas LDL cholesterol measures the cargo they're carrying. These usually track together, but they can disagree: someone can have many small particles carrying less cholesterol each, in which case LDL may look reassuring while apoB doesn't. ApoB is commonly reviewed alongside LDL and non-HDL cholesterol; it isn't part of every standard panel, and how much it adds beyond non-HDL for an individual person is still debated among guideline bodies.

Typical range

  • Adultsunder 90 mg/dL

Source · Mayo Clinic Laboratories (Desirable) (2026)

Reference ranges vary between laboratories, and what is normal for you depends on your own history. Your own lab’s range is the one printed on your report.

Worth asking your clinician

  • Does my apoB agree with my LDL and non-HDL results, or is there a mismatch worth discussing?
  • For someone with my risk profile, how much extra information does apoB give you?
  • Is this a number worth rechecking over time, or is once enough for now?