What is a healthy ApoB level?
There is no fixed universal 'healthy' ApoB value, but the research indicates that below 82 mg/dL the risk of stroke is already measurably lower and that treatment aimed at reducing ApoB protects the arteries more effectively than targeting LDL cholesterol alone. Discuss your own target value with your doctor, as it depends on your overall risk profile and any medication you may be taking.
In a large Danish cohort study of more than 104,000 people, a measurable increase in the risk of ischaemic stroke was already observed at ApoB levels above 82 mg/dL. As many as 16.3% of all ischaemic strokes in that population were attributable to ApoB above that level, while elevated LDL cholesterol explained only 6.8%. This suggests that 82 mg/dL is a meaningful lower threshold to keep in mind.
A separate Polish hospital study (nearly 10,600 patients) used 100 mg/dL as the cut-off for 'elevated'. The median ApoB in that population was 78 mg/dL. Notably, patients with the highest cardiovascular risk had on average lower values, most likely because they were already using lipid-lowering medication. This shows that 'normal' values in hospital populations are already influenced by treatment.
ApoB tells you more than LDL cholesterol alone. In nearly a quarter of the patients in the same Polish study, ApoB painted a different picture than LDL cholesterol. This discrepancy arises because ApoB measures the actual number of harmful fat particles in the blood, whereas LDL cholesterol only expresses the amount of cholesterol carried inside those particles. Someone with many small, cholesterol-poor LDL particles can have a 'normal' LDL while their ApoB is too high.
The usefulness of ApoB as a treatment target has concrete supporting evidence. A meta-analysis of 27 studies showed that the absolute reduction in ApoB had the strongest association with shrinkage of narrowings in the coronary arteries (correlation coefficient 0.79), stronger than the reduction in LDL cholesterol (0.57) or non-HDL cholesterol (0.52). ApoB is therefore likely a better gauge of a treatment's effect on arterial plaque build-up.
At a young age, the consequences of a high ApoB are not always visible yet. A small study in Amish children and young adults with an inherited condition that structurally raises ApoB (familial hypercholesterolaemia caused by an ApoB mutation) found no detectable arterial calcification measured at the carotid artery or vascular stiffness. This concerns only 13 carriers, so the study provides no certainty about the long-term risk in this group.
The claims are based on two cohort studies (n=104,618 and n=10,597), one meta-analysis of 27 studies on plaque regression, and one small study (n=13 carriers of an inherited mutation). No large randomised trials on ApoB target values are included in the source. The evidence is associative in nature; causality in plaque regression is considered probable on the basis of the meta-analysis.