Which lipoprotein is known as the "good" cholesterol that helps lower serum cholesterol levels?

High-density lipoproteins (HDL) are referred to as "good" cholesterol because they play a crucial role in transporting cholesterol away from the arteries and back to the liver, where it can be processed and excreted. This process helps to prevent the accumulation of cholesterol in the arterial walls, which is associated with a reduced risk of cardiovascular diseases. Higher levels of HDL are generally associated with better heart health, and maintaining optimal HDL levels is an important aspect of overall wellness.

In contrast, low-density lipoproteins (LDL) are known as "bad" cholesterol because they can lead to plaque buildup in the arteries, contributing to atherosclerosis. Very low-density lipoproteins (VLDL) are primarily responsible for carrying triglycerides in the bloodstream and are also considered detrimental in excess. Triglycerides themselves are a type of fat found in the blood, and while they are not cholesterol, high levels can also increase cardiovascular risk. Therefore, HDL stands out as the protective lipoprotein that aids in lowering total serum cholesterol levels.