If folate levels in the blood are too high, it indicates that a lot of folic acid is present in the diet, or there might be a deficiency of vitamin B, according to WebMD. If vitamin B is too low, the body cannot process the folate in the blood.
Folic acid, or folate, is in the plasma or red blood cells, and the blood work measures the recent intake of folic acid through the diet, explains WebMD. Folic acid is available in foods such as spinach, liver, whole grain or citrus fruits. It is also in kidney, milk, beast and yeast. Depending on the type of test, a doctor may suggest testing the plasma or the red blood cells for the presence of folic acid, and the most accurate way is to test the red blood cells.
A doctor may suggest a test for folic acid in many cases, including to check for anemia, states WebMD. In this case, the test often occurs in conjunction with a test for vitamin B-12, as the lack of either of these may indicate anemia. Doctors may also do this test to check for malnutrition, to see if treatment for folic acid or vitamin B-12 deficiency is working or to ensure that a pregnant woman has enough folic acid for the baby.