Synonyms: Cobalamin Test, Cyanocobalamin Test

Why It Is Done

* Detect vitamin B12 deficiency anemia.*Diagnose the cause of certain types of anemia.*Diagnose the cause of dementia or other nervous system symptoms, such as tingling or numbness of the arms or legs (peripheral neuropathy).*Determine whether vitamin B12 deficiency anemia is present after a diagnosis of atrophic gastritis has been made.*Help diagnose certain types of leukemia.

Test Overview

A vitamin B12 blood test measures the amount of vitamin B12 in the body. The body needs this B vitamin to make blood cells and to maintain a healthy nervous system.

Vitamin B12 is usually measured at the same time as a folic acid test, because a lack of either one can lead to a form of anemia called megaloblastic anemia. Lack of vitamin B12 also affects the nervous system.

Folic acid (folates)

Folic acid, one of the B vitamins, is important for the normal development of an unborn child (fetus). Folic acid and its closely related compounds, folates, are needed for the production of red and white blood cells and platelets, the formation of genetic material (DNA) in cells, and growth.

Only a small amount of folic acid is stored in the body. To avoid a deficiency, a person must get folic acid regularly from the foods in the diet.

How To Prepare

No special preparation is necessary