Cholesterol is a fatty substance your body needs to rebuild its cells and to make certain hormones. It's carried throughout your body in your bloodstream. Your body only requires a small amount of cholesterol.
When there's too much cholesterol in your bloodstream, you have high cholesterol. This is quite a common condition. Cholesterol levels generally rise with age. High cholesterol can increase your risk of heart disease, stroke, and peripheral vascular disease.
Most of your body's cholesterol (about 80%) is made in your liver. The rest comes from your diet. Dietary cholesterol is found in foods from animal sources, such as eggs, meats, and dairy products. There are two important types of cholesterol you should know about:
- low-density lipoprotein (LDL), or "bad" cholesterol
- high-density lipoprotein (HDL), or "good" cholesterol
Most of the LDL, or "bad," cholesterol circulates in the blood and remains unused. Normally, the liver removes this "extra" cholesterol, but many people have more LDL cholesterol than the liver can handle. LDL cholesterol promotes buildup of harmful plaque (fatty deposits) in the walls of the arteries.
HDL gets its "good" name by picking up LDL cholesterol from the arteries and tissues and carrying it back to the liver, where it can be broken down.