Which lipoprotein is considered unhealthy when levels are elevated?

• A. HDL
• B. LDL
• C. VLDL
• D. Chylomicrons

Answer: (B)

Elevated LDL is most problematic because this lipoprotein delivers cholesterol from the liver to tissues, including the walls of arteries. When LDL levels rise, more cholesterol can accumulate in the arterial intima, where it can become oxidized and taken up by macrophages to form foam cells, leading to atherosclerotic plaques. This plaque buildup narrows and stiffens arteries, increasing the risk of heart attack and stroke.

In contrast, HDL helps remove cholesterol from arteries and shuttle it back to the liver, acting protectively. VLDL and chylomicrons carry triglycerides, and while very high levels can contribute to disease, the classic and most direct association with increased cardiovascular risk is with LDL.