Cholesterol is different from most tests in that it is not used to diagnose or monitor a disease but is used instead to estimate risk of developing a disease — specifically heart disease. Because high blood cholesterol has been associated with hardening of the arteries (atherosclerosis), heart disease, and a raised risk of death from heart attacks, cholesterol testing is considered a routine part of preventive health care.
Cholesterol is tested at more frequent intervals (often several times per year) in people who have been prescribed diet and/or drugs to lower their cholesterol. The test is used to track how well these measures are succeeding in lowering cholesterol to desired levels and in turn lowering the risk of developing heart disease.
Cholesterol testing may be ordered more frequently for those who have one or more risk factors for heart disease. Major risk factors include:
Age (men 45 years or older or women 55 years or older)
Hypertension (blood pressure of 140/90 or higher or taking high blood pressure medications)
Family history of premature heart disease (heart disease in an immediate family member—male relative under age 55 or female relative under age 65)
Pre-existing heart disease or already having had a heart attack
Screening for high cholesterol as part of a lipid profile is recommended for children and young adults. They should be tested once between the ages of 9 and 11 and then again between the ages of 17 and 21. Youth who are at an increased risk of developing heart disease as adults may require additional screening. Some of the risk factors are similar to those in adults and include:
Family history—history of high cholesterol or heart disease in close relatives, particularly if occurring before age 55 in women or 65 in men. If the family history is not known, a cholesterol test is recommended, especially if other risk factors are present.
Being overweight or obese—when the youth's body mass index (BMI) is at or above the 85th percentile, cholesterol testing is recommended. The BMI should be calculated at least once a year by the youth's health care provider. For an obese youth (one whose BMI is at or above the 95th percentile), laboratory tests to measure cholesterol levels may be recommended every 2 years.
Consuming excessive amounts of cholesterol, saturated fats, and trans fats
High blood pressure (hypertension)
High-risk children should have their first cholesterol test between 2 and 10 years old, according to the American Academy of Pediatrics. Children younger than 2 years old are too young to be tested. If the initial results are not worrisome, the fasting test should be done again in three to five years.
For adults, in a routine setting where testing is done to screen for risk, the test results are grouped in three categories of risk:
Desirable: A cholesterol below 200 mg/dL (5.18 mmol/L) is considered desirable and reflects a low risk of heart disease.
Borderline high: A cholesterol of 200 to 239 mg/dL (5.18 to 6.18 mmol/L) is considered to reflect moderate risk. A health care provider may decide to order a lipid profile to see if the high cholesterol is due to the amount of bad cholesterol (high LDL-C) or good cholesterol (high HDL-C). Depending on the results of the lipid profile (and any other risk factors), a decision will be made about whether treatment, including lifestyle changes, is necessary.
High risk: A cholesterol greater than or equal to 240 mg/dL (6.22 mmol/L) is considered high risk. A health care provider may order a lipid profile (as well as other tests) to try to determine the cause of the high cholesterol. Once the cause is known, an appropriate treatment will be prescribed.
For children and adolescents:
A cholesterol below 170 mg/dL (4.40 mmol/L) is acceptable.
A result of 170-199 mg/dL (4.40-5.16 mmol/L) is borderline.
A total cholesterol reading greater than or equal to 200 mg/dL (5.17 mmol/L) is considered high.
For young adults:
A cholesterol below 190 mg/dL (4.92 mmol/L) is acceptable.
A result of 190-224 mg/dL (4.92-5.80 mmol/L) is borderline.
A total cholesterol greater than or equal to 225 mg/dL (5.82 mmol/L) is considered high.
In a treatment setting, testing is used to see how much cholesterol is decreasing as a result of treatment. The goal for the amount of change or the final (target) value will be set by the health care provider. The target value is usually based on LDL-C.
Cholesterol should be measured when a person is not ill. Blood cholesterol is temporarily low during acute illness, immediately following a heart attack, or during stress (like from surgery or an accident). Wait at least six weeks after any illness to have cholesterol measured.
There is some debate about whether very low cholesterol is bad. Low cholesterol (less than 100 mg/dL (2.59 mmol/L)) is often seen when there is an existing problem like malnutrition, liver disease, or cancer. However there is no evidence that low cholesterol causes any of these problems.
Cholesterol is typically high during pregnancy. Women should wait at least six weeks after having a baby to have cholesterol measured.
Some drugs that are known to increase cholesterol levels include anabolic steroids, beta blockers, epinephrine, oral contraceptives, and vitamin D.
This article was last reviewed on August 15, 2013. | This article was last modified on September 24, 2015.
The review date indicates when the article was last reviewed from beginning to end to ensure that it reflects the most current science. A review may not require any modifications to the article, so the two dates may not always agree.
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