Cholesterol is a waxy substance your body uses to protect nerves, make cell tissues and produce certain hormones. Your liver makes all the cholesterol your body needs. Cholesterol can also come directly in the food you eat (such as eggs, meats and dairy products). Too much cholesterol can have negative impacts on your health.
While some cholesterol is needed for good health, too much cholesterol in your blood can raise your risk of having a heart attack or stroke.
The extra cholesterol in your blood may be stored in your arteries (blood vessels that carry blood from your heart to the rest of your body). Buildup of cholesterol in your arteries is known as plaque. It will cause your arteries to narrow and harden (called atherosclerosis). Large deposits of cholesterol can completely block an artery. Cholesterol plaques can also split open, leading to formation of a blood clot that blocks the flow of blood.
If an artery that supplies blood to the muscles in your heart becomes blocked, a heart attack can occur. If an artery that supplies blood to your brain becomes blocked, a stroke can occur.
You can't tell if you have high cholesterol without having it checked. All men aged 35 and older and women aged 45 and older with other heart disease risk factors should have their cholesterol checked every 5 years. If your cholesterol level is high or you have other risk factors for heart disease (see the box above), you may need to have it checked sooner and more often.
A blood test known as a lipid panel is usually the way cholesterol is checked.
Yes. Cholesterol travels through the blood in different types of bundles, called lipoproteins.
Low-density lipoprotein (LDL) delivers cholesterol to the body. High-density lipoprotein (HDL) removes cholesterol from the bloodstream.
This explains why too much LDL cholesterol is bad for the body, and why a high level of HDL is good. The balance between the types of cholesterol tells you what your cholesterol level means (see the box below).
For example, if your total cholesterol level is high because of a high LDL level, you may be at higher risk of heart disease or stroke. If your total level is high only because of a high HDL level, you're probably not at higher risk.
If you have high cholesterol, it may be necessary for you to make some lifestyle changes. If you smoke, quit. Exercise regularly. If you're overweight, losing just 5 to 10 pounds can help improve your cholesterol levels. Make sure to eat plenty of fruits, vegetables, whole grains and fish- all of which promote heart health. Avoid saturated and trans fats, which can raise cholesterol levels. Also limit your overall cholesterol intake to less than 300 milligrams per day and 200 milligrams if you have heart disease.
More information is available in our handout on how to make healthier food choices.
Depending on your risk factors, if healthy eating and exercise don't work to lower your cholesterol level, your doctor may suggest medicine.
For more information about this topic, see our handout on cholesterol-lowering medicines.