Apolipoprotein B (ApoB) Unit Converter

Apolipoprotein B (ApoB) is a protein that forms the structural backbone of several lipoproteins that transport cholesterol and fats through your bloodstream. It is the primary protein component of low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and lipoprotein(a).

Each of these lipoprotein particles contains exactly one ApoB molecule. This means that measuring ApoB directly counts the total number of atherogenic (artery-clogging) particles in your blood, rather than just measuring the cholesterol content within those particles.

There are two forms of ApoB: ApoB-100 (produced by the liver) and ApoB-48 (produced in the intestine). Most clinical ApoB tests measure the total of both forms, though ApoB-100 makes up the vast majority of circulating ApoB.

ApoB-100 is synthesized by the liver and released into the bloodstream as part of VLDL particles. ApoB-48 is produced in the small intestine and incorporated into chylomicrons, which transport dietary fats from the gut to the liver.