Cholesterol is a waxy, fat-like substance that's found in your blood and every cell of your body. You need some cholesterol to keep your cells and organs healthy. Your liver makes all the cholesterol your body needs. But you can also get cholesterol from the foods you eat, especially meat, eggs, poultry, and dairy products. Foods that are high in dietary fat can also make your liver produce more cholesterol.

There are two main types of cholesterol: low-density lipoprotein (LDL), or "bad" cholesterol, and high-density lipoprotein (HDL), or "good" cholesterol. A cholesterol test is a blood test that measures the amount of each type of cholesterol and certain fats in your blood.

Too much LDL cholesterol in your blood may put you at risk for heart disease and other serious conditions. High LDL levels can cause the build-up of plaque, a fatty substance that narrows the arteries and blocks blood from flowing normally. When blood flow to the heart is blocked, it can cause a heart attack. When blood flow to the brain is blocked, it can lead to stroke and peripheral artery disease.

Other names for a cholesterol test: Lipid profile, Lipid panel

If you have high cholesterol, you may not experience any symptoms at all, but you could be at significant risk for heart disease. A cholesterol test can give your health care provider important information about the cholesterol levels in your blood. The test measures:

• LDL levels. Also known as the "bad" cholesterol, LDL is the main source of blockages in the arteries.
• HDL levels. Considered the "good" cholesterol, HDL helps get rid of "bad" LDL cholesterol.
• Total cholesterol. The combined amount of low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol in your blood.
• Triglycerides A type of fat found in your blood. According to some studies, high levels of triglycerides may increase the risk of heart disease, especially in women.
• VLDL levels. Very low-density lipoprotein (VLDL) is another type of "bad" cholesterol. Development of plaque on the arteries has been linked to high VLDL levels. It's not easy to measure VLDL, so most of the time these levels are estimated based on triglyceride measurements.

Your doctor may order a cholesterol test as part of a routine exam, or if you have a family history of heart disease or one or more of the following risk factors:

• High blood pressure
• Type 2 diabetes
• Smoking
• Excess weight or obesity
• Lack of physical activity
• A diet high in saturated fat

Your age may also be a factor, because your risk for heart disease increases as you get older.

A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Cholesterol tests are usually done in the morning, as you may be asked to refrain from eating for several hours prior to the test.

Cholesterol is usually measured in milligrams (mg) of cholesterol per deciliter (dL) of blood. The information below shows how the different types of cholesterol measurements are categorized.

Total Cholesterol Level

• Less than 200 mg/dL
• 200-239 mg/dL
• 240 mg/dL and higher

Total Cholesterol Category

• Desirable
• Borderline High
• High

LDL Cholesterol Level

• Less than 100 mg/dL
• 100-129 mg/dL
• 130-159 mg/dL
• 160-189 mg/dL
• 190 mg/dL and higher

LDL Cholesterol Category

• Optimal
• Near optimal/above optimal
• Borderline high
• High
• Very High

HDL Cholesterol Level

• Less than 40 mg/dL
• 40-59 mg/dL
• 60 mg/dL and higher

HDL Cholesterol Category

• A major risk factor for heart disease
• The higher the better
• Considered protective against heart disease

A healthy cholesterol range for you may depend on your age, family history, lifestyle, and other risk factors. In general, low LDL levels and high HDL cholesterol levels are good for heart health. High levels of triglycerides may also put you at risk for heart disease.

The LDL on your results may say "calculated" which means it includes a calculation of total cholesterol, HDL, and triglycerides. Your LDL level may also be measured "directly," without using other measurements. Regardless, you want your LDL number to be low.

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