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How does HDL cholesterol help protect arteries from atherosclerosis?
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cardiovascular disease
This micrograph shows a cross section of a coronary artery narrowed by an atherosclerotic plaque (purplish matter inside the artery). Most heart attacks are caused by the rupture of an atherosclerotic plaque, which triggers the formation of a clot that abruptly blocks blood flow to part of the heart muscle.
High-density lipoproteins (HDL), often referred to as "good cholesterol," help protect arteries from atherosclerosis by facilitating the removal of excess cholesterol from the body's tissues.12
Unlike low-density lipoproteins (LDL), which transport cholesterol to tissues and contribute to the buildup of fatty deposits in arterial walls, HDL functions as a transport mechanism for reverse cholesterol movement. The process works as follows:23
- Collection: HDL particles pick up excess or unused cholesterol from the surface membranes of cells throughout the body.24
- Conversion: Through the action of the enzyme lecithin cholesterol acyltransferase (LCAT), the collected cholesterol is converted into esters.4
- Excretion: HDL delivers this cholesterol back to the liver, where it is metabolized into bile acids and salts, eventually being eliminated from the body through the intestine.34
By maintaining this cholesterol balance and preventing the accumulation of fatty substances in the interior walls of blood vessels, HDL helps retard or reduce the atherosclerotic process.23