Keeping your cholesterol levels healthy is a great way to keep your heart healthy – and lower your chances of getting heart disease or having a stroke. Cholesterol is a fatty substance that occurs naturally in the body. It performs several vital functions. It is needed to make the walls surrounding the body's cells and is the basic material that is converted to certain hormones. Your body makes all the cholesterol you need. You need only a small amount of fat in your diet to make enough cholesterol to stay healthy.

The fat and cholesterol you eat are absorbed in the intestine and transported to the liver. The liver converts fat into cholesterol, and releases cholesterol into the bloodstream. There are two main types of cholesterol: low-density lipoprotein (LDL) cholesterol (the "bad" cholesterol) and high-density lipoprotein (HDL) cholesterol (the "good" cholesterol).

High levels of LDL cholesterol are linked to atherosclerosis. Atherosclerosis is the hardening of the arteries. It occurs when fat, cholesterol, and other substances build up in the walls of arteries and form hard structures called plaques.

Atherosclerosis affecting the heart is called coronary artery disease, and it can cause a heart attack. When atherosclerosis blocks arteries that supply blood to the brain, it can cause a stroke.

A low LDL cholesterol level is considered good for your heart health. High levels of HDL cholesterol actually protect against heart attacks and strokes by removing cholesterol from the arteries and bringing it back to the liver.

Low HDL cholesterol puts you at higher risk for heart disease. People with high blood triglycerides usually also have lower HDL cholesterol. Genetic factors, type 2 diabetes, and certain drugs, such as beta-blockers and anabolic steroids, also lower HDL cholesterol levels.

Smoking, being overweight and being sedentary can all result in lower HDL cholesterol. The normal range for total cholesterol is 200 or less.

You also need to know your "healthy" HDL cholesterol and "bad" LDL cholesterol numbers. The optimal range for HDL cholesterol is more than 60 and LDL cholesterol should be less than 100.

High total cholesterol, high LDL, or low HDL may increase your risk for a heart attack or stroke. There are no definite symptoms of high cholesterol, so it's important to see your doctor and know your cholesterol numbers. You may help to prevent high cholesterol by staying on a healthy diet and exercising daily.

A diet high in saturated and trans fats raises LDL cholesterol. Avoid high-fat foods (eggs, fatty red meats, palm or coconut oil, dairy products made with whole milk). Instead eat more fresh fruits and vegetables, whole-grain breads and cereals, and low-fat dairy products.

Cholesterol levels should be measured at least once every five years in everyone over age 20. The screening test that is usually performed is a blood test called a lipid profile. Experts recommend that men ages 35 and older and women ages 45 and older be more frequently screened for lipid disorders.