What is the primary role of HDL in cholesterol transport?

• A. Take cholesterol away from peripheral tissues to the liver
• B. Deliver cholesterol to peripheral tissues
• C. Transport triglycerides to adipose tissue
• D. Transport cholesterol to the brain

Answer: (B)

HDL’s main job is reverse cholesterol transport: it scavenges cholesterol from peripheral tissues (including macrophages in artery walls) and returns it to the liver, where the cholesterol can be processed and excreted into bile or repurposed. This removal of cholesterol from sites where it can contribute to atherosclerosis is what HDL is best known for. In contrast, other lipoproteins have different roles: LDL delivers cholesterol to tissues that need it, while VLDL carries triglycerides to various tissues. Transport of cholesterol to the brain is not HDL’s primary function, partly because the brain is largely insulated by the blood–brain barrier. So the best description is HDL moving cholesterol away from peripheral tissues back to the liver for disposal or reuse.