Cholesterol test

Overview

A complete cholesterol test is a blood test. It can measure the amount of cholesterol and fats called triglycerides in blood. This test also is called a lipid panel or a lipid profile.

A cholesterol test can help your healthcare professional figure out your risk of narrowed or blocked arteries. Cholesterol, fats and other substances can build up in the arteries over time. This buildup is called plaque. Plaque can cause narrowed or blocked arteries throughout the body, also called atherosclerosis.

A cholesterol test is an important way to check your health. High cholesterol levels often are a key risk factor for a common type of heart disease called coronary artery disease. Coronary artery disease can lead to conditions such as heart attack and stroke.

Why it's done

High cholesterol rarely causes symptoms. A complete cholesterol test can help find out whether your cholesterol is high. It also can help gauge your risk of heart and blood vessel diseases.

A complete cholesterol test measures the amounts of four types of fats in blood:

• Total cholesterol. This is a sum of the blood's cholesterol content.
• Low-density lipoprotein (LDL) cholesterol. This is called the "bad" cholesterol. Too much of it in the blood causes the buildup of plaque in arteries. Plaque limits blood flow. Sometimes, plaque also breaks apart. That can lead to a heart attack or stroke.
• High-density lipoprotein (HDL) cholesterol. This is called the "good" cholesterol. It helps carry away LDL cholesterol, the bad cholesterol. That keeps arteries open and blood flowing more freely.
• Triglycerides. Triglycerides are a type of fat in the blood. When you eat, your body converts calories it doesn't need into triglycerides. Then triglycerides are stored in fat cells. High triglyceride levels are linked with many risk factors. These include being overweight, eating too many sweets or drinking too much alcohol. Smoking, being inactive or having diabetes also may raise the risk of high triglycerides.

Who should get a cholesterol test?

The American Heart Association recommends that children get checked for high cholesterol once between the ages of 9 and 11. This also is called cholesterol screening. Screening may start earlier if a child has a family history of high cholesterol, heart attack or stroke. Screening also may start earlier if a child has conditions such as diabetes or obesity.

The next cholesterol screening is recommended between the ages of 17 and 21. After that, many adults get their cholesterol checked every 4 to 6 years. People who have health conditions such as high blood pressure or diabetes may need to get screened more often. So might those who have a family history of high cholesterol or heart disease.

You may need more-frequent testing if:

• Your initial test results show that your cholesterol is high.
• You already have coronary artery disease.
• You take medicines that lower cholesterol.

You also may need testing more often if you have a higher risk of coronary artery disease because you:

• Have a family history of high cholesterol or heart attack.
• Are overweight.
• Smoke cigarettes.
• Have diabetes.
• Have high blood pressure.
• Don't get enough physical activity.
• Don't eat a nutritious diet.

People who take medicine for high cholesterol need regular cholesterol testing. Testing helps their healthcare professionals track how well their treatments are working.

Risks

There's little risk in getting a cholesterol test. You might have soreness or tenderness around the site where your blood is taken. Rarely, the site can become infected.

How you prepare

In general, you don't have food or liquids other than water for about 9 to 12 hours before the test. This is called fasting. Some cholesterol tests don't require fasting, so follow your healthcare professional's instructions.

What you can expect

During

A cholesterol test is a blood test. It's usually done in the morning if you fast overnight. Blood is taken from a vein, usually from your arm.

Before the needle is inserted, your healthcare professional cleans the puncture site with antiseptic. The healthcare professional also wraps an elastic band around your upper arm. This causes the veins in your arm to fill with blood.

When the needle is inserted, you'll likely feel a brief sting. Then a small amount of blood is collected in a vial or syringe. The elastic band is then removed from your arm to restore blood flow, and blood keeps flowing into the vial. Once enough blood is collected, your healthcare professional removes the needle and covers the puncture site with a bandage.

The blood test likely will take a couple of minutes or less. You'll likely have little pain or bleeding.

After

You don't need to take any safety measures after a cholesterol test. You should be able to drive yourself home and do all your basic activities. If you've been fasting, you might want to bring a snack to eat after your cholesterol test is done.

Results

In the United States, cholesterol levels are measured in milligrams (mg) of cholesterol per deciliter (dL) of blood. In Canada and many European countries, cholesterol levels are measured in millimoles per liter (mmol/L). To understand your test results, use these general guidelines.

Total cholesterol(U.S. and some other countries)	Total cholesterol*(Canada and most of Europe)
Below 200 mg/dL	Below 5.18 mmol/L	Desirable
200-239 mg/dL	5.18-6.18 mmol/L	Borderline high
240 mg/dL and above	Above 6.18 mmol/L	High

LDL cholesterol(U.S. and some other countries)	LDL cholesterol*(Canada and most of Europe)
Below 70 mg/dL	Below 1.8 mmol/L	Desirable for people who have coronary artery disease or other forms of atherosclerosis. Optimal for people at high risk or very high risk of coronary artery disease or other forms of atherosclerosis.
Below 100 mg/dL	Below 2.6 mmol/L	Optimal for healthy people without coronary artery disease.
100-129 mg/dL	2.6-3.3 mmol/L	Near optimal for people who do not have coronary artery disease. High if there is coronary artery disease or other forms of atherosclerosis.
130-159 mg/dL	3.4-4.1 mmol/L	Borderline high for people who do not have coronary artery disease. High if there is coronary artery disease or other forms of atherosclerosis.
160-189 mg/dL	4.1-4.9 mmol/L	High for people who do not have coronary artery disease. Very high if there is coronary artery disease or other forms of atherosclerosis.
190 mg/dL and above	Above 4.9 mmol/L	Very high.

Treatment choices to reach optimal LDL levels should be tailored to your needs. Work with your healthcare professional to find out what LDL level is best for you.

HDL cholesterol(U.S. and some other countries)	HDL cholesterol*(Canada and most of Europe)
Below 40 mg/dL, men Below 50 mg/dL, women	Below 1 mmol/L, men Below 1.3 mmol/L, women	Poor
40-59 mg/dL, men 50-59 mg/dL, women	1-1.5 mmol/L, men 1.3-1.5 mmol/L, women	Better
60 mg/dL and above	Above 1.5 mmol/L	Best

Triglycerides(U.S. and some other countries)	Triglycerides*(Canada and most of Europe)
Below 150 mg/dL	Below 1.7 mmol/L	Desirable
150-199 mg/dL	1.7-2.2 mmol/L	Borderline high
200-499 mg/dL	2.3-5.6 mmol/L	High
500 mg/dL and above	Above 5.6 mmol/L	Very high

*Canadian and European guidelines differ slightly from U.S. guidelines. These conversions are based on U.S. guidelines.

If your results show that your cholesterol level is not as expected, you might be able to improve your cholesterol with lifestyle changes, medicine or both. Take the following steps:

• Eat a diet low in saturated fats and trans fats and rich in legumes, vegetables and other healthy choices.
• Move more each day.
• If you smoke, quit. This may help raise HDL cholesterol, the good cholesterol.

You may need medicines that help lower cholesterol if lifestyle changes aren't enough. You also may need medicine if you have a history of heart disease or cholesterol levels that are far outside the standard range. Talk with your healthcare professional about the best way for you to lower your cholesterol.