Folate-deficiency anemia is a decrease in red blood cells (anemia) due to a lack of folate. Folate is a type of B vitamin. It is also called folic acid.

Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues.

Folate (folic acid) is needed for red blood cells to form and grow. You can get folate by eating green leafy vegetables and liver. However, your body does not store folate in large amounts. So, you need to eat plenty of folate-rich foods to maintain normal levels of this vitamin. 

In folate-deficiency anemia, the red  blood cells are abnormally large. Such cells are called megalocytes. They are also called megaloblasts. They are seen in the bone marrow. This is why this anemia is also called megaloblastic anemia.

Causes of this type of anemia include:

• Too little folic acid in your diet
• Hemolytic anemia
• Long-term alcoholism
• Use of certain medications (such as phenytoin [Dilantin], methotrexate, sulfasalazine, triamterene, pyrimethamine, trimethoprim-sulfamethoxazole, and barbiturates)

The following raise your risk for this type of anemia:

• Alcoholism
• Eating overcooked food
• Poor diet (often seen in the poor, the elderly, and people who do not eat fresh fruits or vegetables)
• Pregnancy

Folic acid is needed to help a baby in the womb grow properly. Too little folic acid during pregnancy may lead to birth defects in a baby. For more information see: Folic acid and birth defect prevention

• Fatigue
• Headache
• Pallor
• Sore mouth and tongue

• Complete blood count (CBC)
• Red blood cell folate level

Rarely, a bone marrow examination may be done.

The goal is to identify and treat the cause of the folate deficiency.

You may receive folic acid supplements, taken by mouth or given through a vein. If you have low folate levels because of a problem with your intestines, you make need treatment for the rest of your life.

Diet changes can help boost your folate level. Eat more green, leafy vegetables and citrus fruits.

Anemia usually responds well to treatment within 2 months.

Symptoms of anemia can cause discomfort. In pregnant women, folate deficiency has been associated with neural tube or spinal defects (such as spina bifida) in the infant.

Other, more severe complications may include:

• Curly graying hair
• Increased skin color (pigment)
• Infertility
• Worsening of heart disease or heart failure

Call for an appointment with your health care provider if you have symptoms of folate deficiency anemia.

Eating plenty of folate rich foods can help prevent this condition.

Experts recommend that women take 400 micrograms (mcg) of folic acid every day before you get pregnant through the first 3 months of pregnancy.

Antony AC. Megaloblastic anemias. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 167.