Food is broken down during the digestion process. Fats that you eat are processed in your intestines. They then are taken up to the blood stream to circulate throughout your body to either be used for energy or stored for later use. Fats that reach the liver are converted by a chemical process into cholesterol. There are two types of cholesterol, good and bad. High levels of HDL, or good cholesterol, seem to protect against heart attacks. LDL cholesterol, or bad cholesterol, sticks to the inside walls of arteries and helps form the plaque that can block blood flow to the heart and brain. Statins block the chemical reaction within the liver that leads to production of LDL, resulting in reduced LDL cholesterol levels in the blood.