Coronary heart disease (CHD), also called coronary artery disease, is a condition in which plaque (plak) builds up inside the coronary arteries. These arteries supply oxygen-rich blood to your heart muscle.

Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. When plaque builds up in the arteries, the condition is called atherosclerosis (ATH-er-o-skler-O-sis). The buildup of plaque occurs over many years.
Figure A shows a normal artery with normal blood flow. Figure B shows an artery with plaque buildup.

Over time, plaque hardens and narrows your coronary arteries. This limits the flow of oxygen-rich blood to your heart muscle.

Eventually, an area of plaque can rupture (break open). This causes a blood clot to form on the surface of the plaque. If the clot becomes large enough, it can mostly or completely block blood flow through a coronary artery.
TLC therapeutic lifestyle changes
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Unhealthy blood cholesterol levels. This includes high LDL cholesterol (sometimes called “bad” cholesterol) and low HDL cholesterol (sometimes called “good” cholesterol).
High blood pressure. Blood pressure is considered high if it stays at or above 140/90 mmHg over time. If you have diabetes or chronic kidney disease, high blood pressure is defined as 130/80 mmHg or higher. (The mmHg is millimeters of mercury—the units used to measure blood pressure.)
Smoking. Smoking can damage and tighten blood vessels, lead to unhealthy cholesterol levels, and raise blood pressure. Smoking also can limit how much oxygen reaches the body's tissues.
Insulin resistanceexternal link icon. This condition occurs if the body can't use its own insulin properly. Insulin is a hormone that helps move blood sugar into cells where it's used as an energy source. Insulin resistance may lead to diabetes.
Diabetesexternal link icon. With this disease, the body's blood sugar level is too high because the body doesn't make enough insulin or doesn't use its insulin properly.
Overweight or obesity. The terms “overweight” and “obesity” refer to body weight that’s greater than what is considered healthy for a certain height.
Metabolic syndrome. Metabolic syndrome is the name for a group of risk factors that raises your risk for CHD and other health problems, such as diabetes and stroke.
Lack of physical activity. Lack of physical activity can worsen other risk factors for CHD, such as unhealthy blood cholesterol levels, high blood pressure, diabetes, and overweight or obesity.
Unhealthy diet. An unhealthy diet can raise your risk for CHD. Foods that are high in saturated and trans fats, cholesterol, sodium (salt), and sugar can worsen other risk factors for CHD.
Older age. As you get older, your risk for CHD increases. Genetic or lifestyle factors cause plaque to build up in your
Taking action to control your risk factors can help prevent or delay coronary heart disease (CHD). Your risk for CHD increases with the number of risk factors you have.

One step you can take is to adopt a healthy lifestyle. Following a healthy diet is an important part of a healthy lifestyle.

A healthy diet includes a variety of fruits, vegetables, and whole grains. It also includes lean meats, poultry, fish, beans, and fat-free or low-fat milk or milk products. A healthy diet is low in saturated fat, trans fat, cholesterol, sodium (salt), and added sugar.

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