Folic acid is one of many B vitamins. The body needs folic acid to make red blood cells (RBC), white blood cells (WBC), platelets, genetic material (DNA), and for growth. Folic acid also is important for the normal development of a baby (fetus).
Folic acid concentration can be measured in the liquid portion of blood (serum). This reflects a person's recent intake of folic acid in the diet.
Folic acid is found in foods such as liver, citrus fruits, leafy vegetables, whole grains, cereals with B vitamins, beans, milk, kidney, and yeast.
Folic acid may also be measured in the red blood cells. This test better serves to measure the amount of folic acid stored in the body.
Pregnant women need extra folic acid. Women who do not get enough folic acid before and during pregnancy are more likely to have a child born with a birth defect, such as spina bifida.
Folic acid concentration is measured by means of analysis of a blood sample drawn from the vein in the arm.
Purpose of the test
A folic acid test measures the amount of folic acid in the blood.
Folic acid deficiency can produce a type of anemia called megaloblastic anemia. Severe folic acid deficiency cause a sore tongue, diarrhea, headaches, weakness, forgetfulness, and fatigue.
Reference range values
20.61 – 70 nmol/L
High levels of B12 and folate are not usual. They can be seen in conditions such as leukemia or liver dysfunction. High folate levels may be seen with pernicious anemia and with vegetarian diets.
Some drugs can decrease B12 and folic acid levels including oral contraceptives, estrogens, alcohol, and some antibiotics.
B12 and/or folate deficiencies can be caused by:
• Insufficient intake. Very rare. Cases appear among vegetarians.
• Malabsorption, due to:
o Celiac disease
o Bacterial overgrowth in the stomach and intestines
o Reduced stomach acid production
o Pernicious anemia. This is the most common cause of B12 deficiency.
o Surgery that removes part of the stomach or the intestines may greatly decrease absorption.
• Increased loss, due to:
o Liver and kidney disease
o Anti-seizure medications such as phenytoin, metformin and methotrexate
• Increased need due to pregnancy.