Folic Acid

Results

A folic acid test measures the amount of folic acid in the blood. Normal values vary from lab to lab.

Folate in liquid portion (plasma) of blood

Adult	2–20 nanograms per milliliter (ng/mL)	4–45 nanomoles per liter (nmol/L) (SI units)
Children	5–21 ng/mL	11–47 nmol/L

 

Folate in red blood cells

Adult	140–628 ng/mL	317–1422 nmol/L (SI units)
Children	More than 160 ng/mL	More than 362 nmol/L

High values

• High levels of folic acid in the blood may mean that you eat a diet rich in folic acid, take vitamins, or take folic acid pills. Consuming more folic acid than the body needs does not cause problems.
• High folic acid levels can also mean a vitamin B₁₂ deficiency. Body cells need vitamin B₁₂ to use folic acid. Therefore, if vitamin B₁₂ levels are very low, folic acid cannot be used by the cells, and high levels of it may build up in the blood. However, a folic acid test is not a reliable way to test for a vitamin B₁₂ deficiency.

Low values

• Low folic acid levels can mean you have a problem with your diet, alcohol dependence, or an eating disorder such as anorexia nervosa.
• Low folic acid levels can also mean you have a problem absorbing or using folic acid, such as a vitamin C deficiency, liver disease, celiac disease, sprue, or Crohn's disease.
• Low folic acid levels can cause problems for certain people. For example:
  • A pregnant woman needs extra folic acid for her growing baby.
  • People who have hemolytic anemia, a condition that causes the rapid destruction of red blood cells, need more folic acid to make more red blood cells.
  • People with certain conditions, such as kidney failure and some types of cancer, may use up folic acid quickly. They may need their blood to be cleaned using a machine (kidney dialysis).

Go to previous section	Go to top of page	Go to next section
Author:	Jan Nissl, RN, BS	Last Updated: March 5, 2007
Medical Review:	E. Gregory Thompson, MD - Internal Medicine Brian Leber, MDCM, FRCPC - Hematology
© 1995-2008 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.