What is cholesterol?
Cholesterol is a waxy, fatty substance, known as a lipid, that is made in the liver. Your body uses cholesterol to make hormones, vitamin D, and the bile acids that help to digest food. It takes only a small amount of cholesterol to meet these needs, and your liver makes all the cholesterol you need. Cholesterol is also found in some foods that contain animal fats (such as meat, eggs, and dairy).
What is high cholesterol and how does it increase my risk for heart disease?
High cholesterol (also called hypercholesterolemia or hyperlipidemia) means that there is too much cholesterol in your blood. Having high cholesterol does not mean that you have heart disease; however, it increases your risk for getting heart disease or having a heart attack. This is because the excess cholesterol can stick to the walls of the arteries. Over time, this fatty plaque buildup will narrow the arteries causing atherosclerosis. If the arteries that carry blood to your heart (the coronary arteries) are affected, less blood and oxygen can get to your heart. This can cause chest pain ( angina). Eventually the fatty plaque may rupture and block the arteries causing a heart attack. High cholesterol alone does not have any symptoms, which is why it is important to have a cholesterol test.
What are the different types of cholesterol and lipids?
Total cholesterol refers to all of the cholesterol in the blood. Because cholesterol is fatty and blood is watery, the two don't mix. Cholesterol is carried in the blood by lipoproteins, a ball-shaped shell that cholesterol can slip into. The are two main types of lipoproteins that carry cholesterol:
High-density lipoprotein, or HDL cholesterol, is the good kind. It moves easily through the blood and does not stick to the artery walls. HDL helps prevent heart disease by carrying cholesterol away from the arteries to the liver where it can be removed from the body. Think “H” for healthy—with HDL cholesterol, a high level is good.
Low-density lipoprotein, or LDL cholesterol is the bad kind. It tends to stick to the lining of the artery walls, leading to fatty plaque buildup. With LDL cholesterol, a high level is bad because it increases your risk for heart disease.
In addition to cholesterol, triglycerides are another type of fat or lipid found in the blood that can increase your risk of heart disease when present in high amounts.