What's the Difference Between 'Good' and 'Bad' Cholesterol?

Lipoproteins can be thought of as little vehicles that zoom around, transporting fat and cholesterol to the different cells in the body. There are two types, high-density lipoproteins (HDLs) and low-density lipoproteins (LDLs), and these are referred to as good and bad cholesterol, respectively.

HDLs are the denser of the two. They consist mostly of protein, and also contain some cholesterol phospholipids and very little fat.

LDLs, on the other hand, are low-density lipoproteins, consisting of mostly cholesterol.

The healthy type of lipoprotein, HDL, zips around your body, picks up the excess cholesterol that sticks to the inside of your arteries and unloads it to the liver for disposal. Our bodies manufacture HDL in the small intestine and liver.

For its job, LDL does the opposite. It doles out cholesterol to cells that seem to be running short on this waxy substance. The bad news about LDL is that these cholesterol-carrying proteins can infiltrate the walls of arteries, leaving behind cholesterol that eventually turns into plaque – a hard, waxy buildup which can block blood flow in the arteries.

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