by Scheinberg D
(Folate Deficiency; Folacin Deficiency)


Folate deficiency is a low level of folate (vitamin B9) in the body. This vitamin is found in many foods. A form of folate, called folic acid, is also added to foods and in supplements. The body uses this vitamin to build proteins, make DNA, and help form red blood cells.

Scanning Electron Micrograph of Red Blood Cells
Copyright © Nucleus Medical Media, Inc.


This problem may be caused by:

  • Not getting enough folate in the diet
  • Not absorbing enough folate from the digestive tract
  • Needing more folate than normal, such as during pregnancy
  • Procedures or medicine that block absorption or raises the need for folate

Risk Factors

Things that may raise the risk of this problem are:

  • Not getting enough folate in the diet due to:
    • Poor nutrition
    • Long-term need for IV nutrition
    • Alcoholism
  • Having conditions and procedures that affect the body's ability to absorb folate from the digestive tract, such as:
    • Inflammatory bowel disease
    • Celiac disease or other malabsorption disorders
    • Certain medications, such as anticonvulsants and oral contraceptives
    • Bariatric surgery
  • Needing more folate than normal due to:
    • Pregnancy or breastfeeding
    • Growth in infants
    • Cancer
  • Liver disease
  • Chronic hemolytic anemia
  • Kidney dialysis
  • Taking certain medicines, such as methotrexate
  • Elevated homocysteine levels in the blood


Problems may be:

  • Feeling very tired
  • Lack of hunger
  • Headache
  • Pale skin
  • A red, irritated, swollen, and sometimes shiny tongue
  • Mouth sores
  • Shortness of breath and lightheadedness
  • Change in bowel patterns, such as loose stools

Folate deficiency can lead to problems such as:

  • Megaloblastic anemia—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


The doctor will ask about your symptoms and health history. A physical exam will be done. You may also be asked about your diet.

Blood tests will be done to check vitamin B levels. Red blood cell folate levels will also need to be tested.


Any underlying causes may be treated.

The goal of treatment is to increase folate levels. This can be done with a folic acid supplement.


The risk of this problem may be lowered by eating foods that contain folate, such as grains, spinach, and lentils. Supplements may need to be taken by people who are at risk for deficiency, such as pregnant women.


March of Dimes 

Office of Dietary Supplements—National Institutes of Health 


Health Canada 

Healthy U 


Bariatric surgery. EBSCO DynaMed Plus website. Available at:  . Updated October 23, 2017. Accessed November 8, 2017.

Dietary supplement fact sheet: folate. Office of Dietary Supplements website. Available at: Updated April 20, 2016. Accessed November 8, 2017.

Folate deficiency. EBSCO DynaMed Plus website. Available at:  . Updated December 21, 2016. Accessed November 8, 2017.

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