Vitamin B12 test may be used to help diagnose the cause of some central nervous systems disorders, certain anemias, such as pernicious anemia and malabsorption syndromes. It is required for the formation of red blood cells (RBC), tissue and cellular repair and DNA synthesis. It is also essential for proper nerve function.
Vitamin B12 cannot be produced in the body and must be supplied in the diet. Foods that contain vitamin B12 include egg yolks, beef, poultry and fish. Vegans and some vegetarians are susceptible to vitamin B12 deficiency.