At a Glance
Why Get Tested?
To determine risk of developing heart disease
When to Get Tested?
A blood sample drawn from a vein in the arm or from a fingerprick (capillary).
Measurement of LDL cholesterol generally requires an 8-12 hour fast before the sample is taken.
The Test Sample
What is being tested?
LDL is a type of lipoprotein that carries cholesterol in the blood. LDL cholesterol (LDL-C) is considered to be undesirable because it deposits excess cholesterol in the walls of blood vessels and contributes to 'narrowing of the arteries' and heart disease. Hence LDL cholesterol is often termed 'bad' cholesterol. The test for LDL cholesterol measures the amount of cholesterol bound to LDL in blood.
How is the sample collected for testing?
The test for LDL cholesterol uses a blood sample. Most often, the blood sample is collected by venipuncture (using a needle to collect blood from a vein in the arm). Measurement of LDL cholesterol generally requires an 8-12 hour fast before the sample is taken.
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NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.