Munson Health
Folic Acid Deficiency

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by Norwood D

(Folate Deficiency; Folacin Deficiency)



There are several causes of folic acid deficiency, including the following:

Risk Factors

Factors that may increase your risk of developing folic acid deficiency include:


Folic acid deficiency may cause:
Complications from folic acid deficiency include:
  • Megaloblastic anemia—a blood disorder characterized by larger than normal red blood cells
  • Elevated homocysteine levels in the blood—a risk factor for heart disease
  • Neural tube defects that affect fetal spinal cord, brain, and skull development


Your doctor will ask about your symptoms and medical history. A physical exam will be done. A blood test can help confirm a diagnosis of low folate levels and megaloblastic anemia.
It is difficult to distinguish between folic acid deficiency and vitamin B12 deficiency. However, folic acid deficiency is confirmed only by measuring red blood cell (RBC) folate levels in the blood.
It is especially important to confirm a diagnosis of folic acid deficiency before treatment with supplemental folic acid begins. Mistreating an actual vitamin B12 deficiency with supplemental folic acid will mask the vitamin B12 deficiency, meaning the anemia will be corrected, but the neurological damage associated with vitamin B12 deficiency will progress.


March of Dimes

Office of Dietary Supplements



Health Canada

Healthy U



Bariatric surgery. EBSCO DynaMed website. Available at: Updated November 13, 2013. Accessed December 2, 2013.

Dietary supplement fact sheet: folate. Office of Dietary Supplements website.Available at: Updated December 14, 2012. Accessed December 2, 2013.

Folate deficiency. EBSCO DynaMed website. Available at: Updated January 16, 2013. Accessed December 2, 2013.

The Merck Manual of Diagnosis and Therapy. 18th ed. John Wiley & Sons, Inc; 2006.

The Merck Manual of Diagnosis and Therapy. 15th ed. Rahway, NJ: Merck Sharp and Dohme Research Laboratories; 1987.


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