Intro
LDL cholesterol has long been the standard marker for heart disease risk.
But growing evidence suggests ApoB—a measure of particle number—may be more accurate.
Key Points
- LDL measures cholesterol content, not particle count
- ApoB reflects the number of atherogenic particles
- More particles = higher risk, even if LDL looks normal
- ApoB is often a better predictor of cardiovascular events
🚨 Breakout: The Core Problem
Two people can have the same LDL cholesterol—but very different numbers of particles.
Risk follows particle number, not just cholesterol mass.
Background
LDL-C measures how much cholesterol is carried in LDL particles.
ApoB measures how many particles are present.
Each atherogenic particle contains one ApoB molecule—making ApoB a direct particle count.
Mechanism
Atherosclerosis is driven by particles entering the arterial wall.
More particles → more opportunities for plaque formation.
Clinical Implications
- Discordance is common (normal LDL, high ApoB)
- ApoB better reflects metabolic risk
- Increasingly used in modern guidelines
FAQ
Q: Should I replace LDL with ApoB?
A: ApoB is best used alongside traditional lipid testing.
Q: Is ApoB widely available?
A: Yes—most labs can perform it.