ApoB

Cholesterol can't dissolve in blood, so your body ships it inside protein-coated bubbles called lipoproteins. ApoB is the backbone of the ones that reach your artery walls, like LDL, the "bad" cholesterol.

Each of those particles carries exactly one ApoB tag. So your ApoB level is essentially a direct count of how many plaque-building particles are in your blood. HDL, the "good" cholesterol, carries none.

Your ApoB number tells you how many particles are available to slip into artery walls, and that count is one of the clearest levers you have. It often reads heart-attack and stroke risk more accurately than standard LDL cholesterol, because plaque builds up particle by particle. Higher means more particles in play.

The upside is that ApoB responds. It moves with diet, exercise, and medication, so a high number caught early is something you can act on. Read it as a signal alongside your other lipid markers and your overall risk, not a diagnosis. Your clinician can help you set the target that fits you.