HDL-2b is a subclass of high-density lipoprotein (HDL), which is often referred to as "good cholesterol" due to its role in transporting cholesterol from the body's tissues back to the liver for excretion. HDL-2b is characterized by its larger size and higher lipid content compared to other HDL subclasses, particularly HDL-2a and HDL-3. Elevated levels of HDL-2b are associated with a lower risk of cardiovascular diseases, as it is more effective in promoting cholesterol efflux and has anti-inflammatory properties. Measuring HDL-2b can provide additional insights into cardiovascular health beyond total HDL levels.