User: What is cholesterol and bad cholesterol and why would I want to reduce my levels?
Assistant: Cholesterol is a waxy, fat-like substance found in the cells in your body. Your liver makes cholesterol and it is also found in some foods like meat and dairy products. Your body needs certain levels of cholesterol to function, but too much raises the risk of  cardiovascular disease. 

LDL, low-density lipoprotein, is also known as bad cholesterol. It gets it's "bad" name because too high of levels of LDL can lead to a build up of cholesterol in you arteries.  The extra amount of LDL forms plaque and the build up of this plaque in your arteries leads to a condition called, artherosclerosis.  Coronary artery disease happens when the plaque buildup is in the arteries of your heart. It causes the arteries to become hardened and narrowed , which slows down or blocks the blood flow to your heart.  Because your blood carries oxygen to your heart, this means that your heart may not be able to get enough oxygen. This can cause angina or chest pains and may lead to a heat attack if blood flow is completely blocked.