LDL peak size reflects the typical diameter of your LDL particles—essentially whether your cholesterol is carried by larger, buoyant particles (Pattern A) or smaller, denser ones (Pattern B).

This matters because smaller, dense LDL particles tend to behave differently in the body. They circulate longer, penetrate the arterial wall more easily, and are more prone to oxidation—all factors that may increase atherosclerotic risk. Smaller LDL size is also commonly seen alongside elevated triglycerides, low HDL, and insulin resistance, making it a marker of underlying metabolic health.

That said, particle size is secondary to particle number. Much of the risk attributed to small dense LDL is explained by a higher total number of atherogenic particles (captured by ApoB or LDL-P).