Cholesterol test: Uses, what to expect, results
What is a cholesterol test?
A lipid panel or lipid profile measures the amount of cholesterol in the blood.
A cholesterol test is also called a lipid panel or a lipid profile. This blood test measures the amount of cholesterol and triglycerides in the blood.
The amount of cholesterol and triglycerides in the blood can help doctors determine whether or not plaque has built up in a person's arteries.
A complete cholesterol test measures the following four types of fats in the blood:
- Total cholesterol level: The total amount of cholesterol in a person's blood.
- Low-density lipoprotein (LDL) cholesterol: Often referred to as "bad cholesterol," this is the cholesterol that can build up in the arteries, raising the risk of heart attack and stroke.
- High-density lipoprotein (HDL) cholesterol: This cholesterol is called "good cholesterol" because it helps keep the arteries clear of LDL cholesterol.
- Triglycerides: These are fats in the bloodstream that give the body energy. When these fats don't get used, the body stores them. Too many of these fats can be indicators of health problems including heart disease.
Risks of untreated high cholesterol
High cholesterol often has no signs and symptoms but can have devastating health consequences. When there is too much cholesterol in the blood, it builds up in the arteries and can harden. This buildup of plaque narrows the arteries and reduces and slows the blood flow to the heart. If the blood supply to any part of the heart is totally blocked, a heart attack occurs.
What is a cholesterol test used for?
A cholesterol test is a useful tool to assess the risk of heart disease including heart attack and stroke.
The test is used to measure and analyze the amount of fats in the blood. If there is too much cholesterol in the blood, treatment can be started to lower cholesterol levels and reduce the risk of heart disease.
Who should get one? How often?
Everyone should get their cholesterol checked regularly. How often depends on age and certain health risk factors.
An adult with average risk of heart disease should get their cholesterol checked every 4 to 6 years starting at age 20.
Some adults need to test their cholesterol more regularly. Those adults include the following individuals:
- those with a family history of heart disease or high cholesterol
- anyone with a previously high cholesterol test
- people with diabetes
- obese or overweight individuals
- inactive people
- people who eat a high-fat diet
- men over the age of 45
- women over the age of 55
Additionally, children should have their cholesterol tested. The Centers for Disease Control and Prevention (CDC) recommend testing a child's cholesterol levels once between the ages of 9 and 11 and again between the ages of 17 and 21.
Cholesterol testing is generally avoided during puberty because hormones can alter the results of the tests.
What to expect with the test
A cholesterol blood test is similar to other blood tests and may involve a 12-hour fast period prior to the procedure.
Most of the time, cholesterol tests require fasting, which means no food or drink other than water for up to 12 hours prior to the test.
Because of this requirement, most people choose to have their cholesterol test done in the morning.
During and after
A cholesterol test is a fairly simple procedure. It involves drawing blood from a vein and is performed in the same way as most other blood tests.
Prior to drawing blood, a technician will examine the arm to locate a good vein and clean the area with antiseptic. They will then wrap a band around the arm, near where the puncture site will be, to help the vein fill with blood.
The technician will then insert a needle into the vein and blood will collect in a vial. The band will be removed while the needle is still in place. After enough blood is collected, the technician will remove the needle and hold a cotton swab on the site to stop the bleeding. The area may be covered with a small bandage.
After the test, there are no special considerations. Most people are able to go about their normal day immediately following a cholesterol test and can drive themselves home. In very rare cases, the test site may become infected, but this is extremely unusual.
What do the results mean?
The results of the test determine whether the cholesterol levels in the person's blood are healthy.
The results will be broken down into several categories by the type of fat. The results are measured in milligrams of cholesterol per deciliter of blood (mg/dL).
Total cholesterol levels
Having a result less than 200 mg/dL is considered good. Borderline high results range from 200-239 mg/dL. High cholesterol levels are considered to be any number over 240 mg/dL.
HDL cholesterol levels
With HDL, it is higher levels that are desirable. A result below 40 mg/dL is poor. A result between 40 and 59 mg/dL is better, while a reading of 60 mg/dL or higher is the best result.
LDL cholesterol levels
LDL cholesterol recommendations vary based on the health of an individual.
- People with heart disease or diabetes should aim for LDL levels below 70 mg/dL.
- Individuals with no heart disease but who are at higher risk for heart disease need to keep levels below 100 mg/dL.
- For people with no increased risk of heart disease, LDL levels between 100 and 129 mg/dL are near perfect.
- A reading from 130 to 159 mg/dL is considered borderline high for those with no heart disease and high for those where heart disease is present.
- A reading from 160 to 189 mg/dL is considered high for those without heart disease and very high for those with heart disease.
- A reading above 190 mg/dL is considered very high for all groups.
Triglyceride levels are considered desirable when below 150 mg/dL. Between 150 and 199 mg/dL is borderline high. Levels between 200 and 499 mg/dL are considered high. Any level above the upper end of this range is considered very high.
Treatment options for high cholesterol
Having high cholesterol doesn't automatically mean a person will develop heart disease. There are many ways to manage cholesterol levels and lower the risk for developing heart disease.
A doctor can recommend lifestyle changes and medications that can help manage and lower high cholesterol.
Lifestyle changes such as following a healthful diet and losing weight are recommended for people with high cholesterol.
Lifestyle changes for high cholesterol include the following:
- getting enough exercise
- losing weight
- quitting smoking
- following a healthful diet
Sugars and carbohydrates increase triglyceride levels, so eating a healthful diet that is low in saturated fat and dietary cholesterol, low in sugar and carbohydrates and high in soluble fiber is recommended.
Doctors use medication to treat the cholesterol levels of the highest risk individuals. There are several types of drugs available that can help manage cholesterol levels. These drugs include statins, nicotinic acid, fibric acid, and cholesterol absorption inhibitors.
Those that need medication should still follow all lifestyle and dietary recommendations for lowering cholesterol. A combination of lifestyle changes and medication can normally lower cholesterol levels for most people.