When we get more cholesterol than we need - either because our body makes too much or because we eat too many cholesterol-rich foods - the surplus cholesterol circulates in the bloodstream. Along with other fat-like substances, certain kinds of this circulating cholesterol tend to deposit in the inner lining of the blood vessels.

These cholesterol-rich deposits become coated with scar tissue, forming a bump in the blood vessel known as plaque. Plaque buildup can narrow and harden the blood vessel - a process called atherosclerosis, or hardening of the arteries.

Eventually these plaque deposits can build up to significantly reduce or block blood flow, causing a heart attack or stroke. Many people experience chest pain or discomfort from inadequate blood flow to the heart, especially during exercise when the heart needs more oxygen. Smaller plaques can also burst, causing blood flowing over them to clot and clog the blood vessel.

A high blood cholesterol level is especially dangerous for smokers and those with high blood pressure. High blood cholesterol, smoking, and high blood pressure are three factors that increase your risk for heart disease.

• If you have one of these risk factors, you double your risk of heart disease.
• If you have two of these risk factors, your risk for heart disease is four times as high.
• If you have three of these risk factors, your risk is eight times as high.

The good news is that lowering your cholesterol level can help reduce your risk for heart disease. For everyone one percent you lower your cholesterol level, you reduce your risk for heart disease by two percent. And lowering your cholesterol can help prevent heart attacks even if you already have heart disease.