National Heart, Lung & Blood Institute

Your blood cholesterol level is affected not only by what you eat but also by how quickly your body makes LDL cholesterol and disposes of it. In fact, your body makes all the cholesterol it needs, and it is not necessary to take in any additional cholesterol from the foods you eat.

Patients with heart disease typically have too much LDL cholesterol in their blood. Many factors help determine whether your LDL cholesterol level is high or low. The following factors are the most important:

Heredity.

Your genes influence how high your LDL cholesterol is by affecting how fast LDL is made and removed from the blood. One specific form of inherited high cholesterol that affects 1 in 500 people is familial hypercholesterolemia, which often leads to early heart disease. But even if you do not have a specific genetic form of high cholesterol, genes play a role in influencing your LDL cholesterol level.

What you eat.

Two main nutrients in the foods you eat make your LDL cholesterol level go up: saturated fat, a type of fat found mostly in foods that come from animals; and cholesterol, which comes only from animal products. Saturated fat raises your LDL cholesterol level more than anything else in the diet. Eating too much saturated fat and cholesterol is the main reason for high levels of cholesterol and a high rate of heart attacks in the United States. Reducing the amount of saturated fat and cholesterol you eat is a very important step in reducing your blood cholesterol levels.

Weight.

Excess weight tends to increase your LDL cholesterol level. If you are overweight and have a high LDL cholesterol level, losing weight may help you lower it. Weight loss also helps to lower triglycerides and raise HDL.

Physical activity/exercise.

Regular physical activity may lower LDL cholesterol and raise HDL-cholesterol levels.

Age and sex.

Before menopause, women usually have total cholesterol levels that are lower than those of men the same age. As women and men get older, their blood cholesterol levels rise until about 60 to 65 years of age. In women, menopause often causes an increase in their LDL cholesterol and a decrease in their HDL cholesterol level, and after the age of 50, women often have higher total cholesterol levels than men of the same age.

Alcohol.

Alcohol intake increases HDL cholesterol but does not lower LDL cholesterol. Doctors don't know for certain whether alcohol also reduces the risk of heart disease. Drinking too much alcohol can damage the liver and heart muscle, lead to high blood pressure, and raise triglycerides. Because of the risks, alcoholic beverages should not be used as a way to prevent heart disease.

Stress.

Stress over the long term has been shown in several studies to raise blood cholesterol levels. One way that stress may do this is by affecting your habits. For example, when some people are under stress, they console themselves by eating fatty foods. The saturated fat and cholesterol in these foods contribute to higher levels of blood cholesterol.

Source: National Heart, Lung & Blood Institute