ApoB — The Particle Count
One molecule per atherogenic particle
Apolipoprotein B (ApoB) is a surface protein on every atherogenic particle — LDL, VLDL, IDL, Lp(a), chylomicron remnants. There's exactly one ApoB per particle, so measuring ApoB measures particle count directly. It's the cleanest single number we have for cardiovascular risk.
Lower is better — much lower than most people think
Attia, Dayspring, and the preventive-cardiology world target ApoB under 60 mg/dL for aggressive prevention, under 80 mg/dL for average risk. Guideline targets are still creeping down from 100+ historical numbers as trials show cumulative exposure drives plaque formation over decades.
Cumulative ApoB burden predicts disease
It's not your ApoB today — it's your ApoB × years of exposure. Someone with ApoB 120 for 40 years accumulates double the arterial burden of someone with ApoB 60 for the same time. Early intervention compounds hugely, which is why checking ApoB in your 30s matters.
Order the ApoB target tiers
Drag these targets from most to least aggressive.
This step is interactive — open the Thier app to try it.
The test costs nothing extra
ApoB is on most lab menus, usually $5–15, usually covered when ordered. The reason most doctors don't order it isn't cost — it's inertia. If you ask for it you'll generally get it. Most of preventive cardiology is now structured around this number.
Key Takeaway
ApoB is the single best cardiovascular-risk number on a standard lab panel. Your cumulative ApoB exposure over decades shapes your arterial health far more than any single reading. Get the test, track it annually, act when it's elevated.