Molecules that are a combination of fat and protein and that transports fats and fat-like substances, such as cholesterol, in the blood.
Source: GreenFacts
High Density Lipoproteins (HDLs) are produced in the liver. They play an important role in the transport of excess cholesterol out of cells and out of the blood for breakdown in the liver.
This is a process known as reverse cholesterol transport as it effectively reverses the action of Low Density Lipoproteins (LDLs) which are responsible for the transport of cholesterol through the blood to the cells.
Cholesterol not taken up by the cells continues to circulate on LDLs in the blood and may be deposited on the lining of the arteries. This may cause atherosclerosis and a low level of HDLs increases the likelihood of cardiovascular diseases.
HDL cholosterol is known as “good” cholesterol, whereas LDL cholesterol is referred to as “bad” cholesterol.
Source: GreenFacts