Cholesterol is a waxy fat-like substance that is present in all the cells in the body. Our body needs some cholesterol to work properly.
But when cholesterol is high in blood, it can stick to the walls of the arteries and narrow or block them. This puts a person at risk of developing coronary artery disease and other heart diseases.
Cholesterol is made in the liver. It travels through the blood on proteins called lipoproteins.
One type of lipoprotein is LDL, also called bad cholesterol. High LDL levels cause the build-up of cholesterol in the arteries. Another type is called HDL which is also called good cholesterol. It carries cholesterol from other parts of the body and back to the liver. Then the liver removes cholesterol from the body.