This is a fatty substance that plays an important part in cellular health; it is both produced in our livers and obtained from foodstuffs such as organ meat, eggs, cheese, milk and butter. Too much cholesterol, however, is a problem. Because it is carried around the bloodstream, any excess levels are deposited on the walls of veins and arteries; this can cause the blood vessels to narrow, therefore decreasing the blood flow and causing heart problems. There are different forms of cholesterol; `good' and 'bad'. This distinction has to do with how it is carried around the blood. Chemicals called lipoproteins, which are combined fatty proteins are used for transporting the cholesterol in the bloodstream, and HDL (High Density Lipoprotein) cholesterol is known as `good' because any excess can be sent to the liver and dealt with, but LDL (Low Density Lipoprotein) cholesterol cannot be, and remains to potentially clog arteries. Read more about Cholesterol and your health.