Folate deficiency

Definition

Folate deficiency means you have a lower-than-normal amount of folic acid, a type of B vitamin, in your blood.

See also: Folic acid

Alternative Names

Deficiency - folic acid, Folic acid deficiency

Causes, incidence, and risk factors

Folic acid works along with vitamin B12 and vitamin C to help the body break down, use, and create new proteins. The vitamin helps form red blood cells and produce DNA, the building block of the human body, which carries genetic information.

Folic acid is a type of B vitamin. It is water-soluble, which means it cannot be stored in the body. Water-soluble vitamins dissolve in water. Leftover amounts of the vitamin leave the body through the urine.

Because folate is not stored in the body in large amounts, you need a continual supply of this vitamin through your diet to maintain normal levels.

You can get folate by eating green leafy vegetables and liver.

Causes of folate deficiency are:

• Certain medications, such as phenytoin (Dilantin)
• Diseases in which folic acid is not absorbed as well, such as celiac disease (sprue) or alcoholism
• Eating overcooked food
• Poor diet (often seen in the poor, the elderly, and people who do not eat fresh fruits or vegetables)
• Excess folic acid needs during the third trimester of pregnancy
• Hemolytic anemia

Symptoms

Folic acid deficiency may cause:

• Diarrhea
• Gray hair
• Mouth ulcers
• Peptic ulcer
• Poor growth
• Swollen tongue

Signs and tests

Folate deficiency can be diagnosed with a blood test. Pregnant women usually have such blood tests during prenatal checkups.

Complications

Anemia (low red blood cell count) and, in severe cases, low levels of white blood cells and platelets are complications. In folate-deficiency anemia, the red blood cells are abnormally large.

Folic acid is also needed for the development of a healthy fetus. It plays an important part in the development of the fetus' spinal cord and brain. Folic acid deficiency can cause severe birth defects of the brain and spinal cord, known as neural tube defects.

Prevention

The best way to get the daily requirement of all essential vitamins is to eat a balanced diet that contains a variety of foods from the Food Guide Pyramid. Most people in the United States eat enough folic acid because it is plentiful in the food supply.

Folate occurs naturally in the following foods:

• Beans and legumes
• Citrus fruits and juices
• Wheat bran and other whole grains
• Dark green leafy vegetables
• Poultry, pork, and shellfish
• Liver

The Institute of Medicine's Food and Nutrition Board recommends that adults should have 400 micrograms of folate daily. Women capable of becoming pregnant should receive this amount with folic acid supplements, not just fortified foods, to ensure the proper daily intake.

Specific recommendations depend on a person's age, gender, and other factors (such as pregnancy). Many foods now have extra folic acid added to help prevent birth defects.

See Folic acid in diet for the full folic acid requirements by age group.

See Folic acid and birth defect prevention for more information on folic acid requirements during pregnancy.

References

Antony AC. Megaloblastic anemias. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 170.

Hamrick I, Counts SH. Vitamin and mineral supplements. Wellness and Prevention. 2008;35:729-747.