Not eating enough raw leafy vegetables and citrus fruits can cause folate deficiency.
Anemia can develop, causing fatigue, paleness, irritability, shortness of breath, and dizziness.
A severe deficiency may result in a red and sore tongue, diarrhea, a reduced sense of taste, depression, confusion, and dementia.
If a pregnant woman has folate deficiency, the risk of having an infant with a birth defect of the spinal cord or brain is increased.
The diagnosis is based on blood tests.
Folate supplements taken by mouth usually correct the deficiency.
Folate is a B vitamin Overview of Vitamins Vitamins are a vital part of a healthy diet. The recommended dietary allowance (RDA)—the amount most healthy people need each day to remain healthy—has been determined for most vitamins. A safe... read more . Along with vitamin B12, folate is necessary for the formation of normal red blood cells Formation of Blood Cells Red blood cells, most white blood cells, and platelets are produced in the bone marrow, the soft fatty tissue inside bone cavities. Two types of white blood cells, T and B cells ( lymphocytes)... read more and the synthesis of DNA (deoxyribonucleic acid), which is the genetic material of cells. Folate is also necessary for normal development of a fetus’s nervous system.
Good sources of folate include raw green leafy vegetables, asparagus, broccoli, fruits (especially citrus), liver, other organ meats, dried yeast, and enriched breads, pastas, and cereals. Extensive cooking destroys 50 to 95% of the folate in food.
In the United States and Canada, folate is added to enrich foods made from grains. Folate in supplements or in enriched foods is easier for the body to absorb than the folate that occurs naturally in food.
Women who are pregnant or who could become pregnant should take folate supplements to reduce the risk of having an infant with a birth defect, mainly neural tube defects Neural Tube Defects and Spina Bifida Neural tube defects are a certain type of birth defect of the brain, spine, and/or spinal cord. Neural tube defects can result in nerve damage, learning disabilities, paralysis, and death. The... read more . Women who have had a baby with a neural tube defect are often prescribed higher doses of folate.
Women who are taking both oral contraceptives and antiseizure drugs may need to take folate supplements. Antiseizure drugs can make oral contraceptives less effective. Folate supplements can help maintain the effectiveness of oral contraceptives.
Folate supplements do not protect against coronary artery disease or stroke. There is no evidence that folate supplements reduce or increase the risk of various cancers. Folate supplements do not seem to improve cognitive function in older adults.
Folate is generally not toxic.
Causes of Folate Deficiency
Folate deficiency may result from
Inadequate consumption of folate (usually in people who drink too much alcohol or are undernourished)
Impaired absorption (resulting from, for example, a malabsorption disorder such as celiac disease Celiac Disease Celiac disease is a hereditary intolerance to gluten (a protein found in wheat, barley, and rye) that causes characteristic changes in the lining of the small intestine, resulting in malabsorption... read more
or use of certain drugs)An increased need for folate (for example, due to pregnancy or breastfeeding)
People who drink large amounts of alcohol Alcohol Use Alcohol (ethanol) is a depressant (it slows down brain and nervous system functioning). Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma,... read more do not consume enough folate because they often substitute alcohol for food. Such people are often generally undernourished Undernutrition Undernutrition is a deficiency of calories or of one or more essential nutrients. Undernutrition may develop because people cannot obtain or prepare food, have a disorder that makes eating or... read more 
. Alcohol consumed in large amounts also interferes with the absorption and processing (metabolism) of folate.
Malabsorption disorders Overview of Malabsorption Malabsorption syndrome refers to a number of disorders in which nutrients from food are not absorbed properly in the small intestine. Certain disorders, infections, and surgical procedures can... read more (such as celiac disease) interfere with absorption of folate.
Women who are pregnant or breastfeeding and people undergoing dialysis may develop this deficiency because their need for folate is increased.
Some drugs decrease the absorption of this vitamin. They include
Other drugs interfere with the metabolism of folate. They include
Methotrexate (used to treat cancer and rheumatoid arthritis)
Triamterene (used to treat high blood pressure)
Metformin (used to treat diabetes)
Trimethoprim-sulfamethoxazole (an antibiotic)
Symptoms of Folate Deficiency
Folate deficiency results in anemia Vitamin Deficiency Anemia Vitamin deficiency anemia results from low or depleted levels of vitamin B12 or folate (folic acid). People may be weak, short of breath, and pale. Nerves may malfunction. Blood tests can detect... read more that develops gradually and may be more severe than symptoms suggest. Fatigue may be the first symptom.
In addition to the general symptoms of anemia (such as paleness, irritability, shortness of breath, and dizziness), folate deficiency, if severe, may result in a red and sore tongue, diarrhea, a reduced sense of taste, weight loss, and depression.
If a pregnant woman has folate deficiency, the risk of having an infant with a birth defect of the spinal cord or brain (neural tube defect Neural Tube Defects and Spina Bifida Neural tube defects are a certain type of birth defect of the brain, spine, and/or spinal cord. Neural tube defects can result in nerve damage, learning disabilities, paralysis, and death. The... read more ) is increased.
Diagnosis of Folate Deficiency
Blood tests
If a blood test detects large red blood cells in people who have anemia Vitamin Deficiency Anemia Vitamin deficiency anemia results from low or depleted levels of vitamin B12 or folate (folic acid). People may be weak, short of breath, and pale. Nerves may malfunction. Blood tests can detect... read more or who are undernourished Undernutrition Undernutrition is a deficiency of calories or of one or more essential nutrients. Undernutrition may develop because people cannot obtain or prepare food, have a disorder that makes eating or... read more , doctors measure the folate level in a blood sample. A low level indicates folate deficiency.
Doctors also measure the vitamin B12 level to rule out vitamin B12 deficiency Vitamin B12 Deficiency Vitamin B12 deficiency can occur in vegans who do not take supplements or as a result of an absorption disorder. Anemia develops, causing paleness, weakness, fatigue, and, if severe, shortness... read more because this deficiency can also result in anemia and large red blood cells. Doctors must rule out vitamin B12 deficiency before they treat folate deficiency in people with anemia. If people with vitamin B12 deficiency are treated with folate, the anemia may lessen. But folate supplementation does not relieve the nerve damage due to vitamin B12 deficiency and may even make it worse.
Prevention and Treatment of Folate Deficiency
Folate supplements
To help prevent folate deficiency, people who are taking drugs that interfere with the absorption or metabolism of folate should take a folate supplement.
Taking daily doses of a folate supplement by mouth effectively treats the deficiency.
Drugs Mentioned In This Article
| Generic Name | Select Brand Names |
|---|---|
phenytoin |
Dilantin, Dilantin Infatabs, Dilantin-125, Phenytek |
phenobarbital |
Luminal, Sezaby |
methotrexate |
Otrexup, Rasuvo, RediTrex, Rheumatrex, Trexall, Xatmep |
triamterene |
Dyrenium |
metformin |
Fortamet, Glucophage, Glucophage XR, Glumetza, Riomet, RIOMET ER |
trimethoprim |
Primsol, Proloprim, TRIMPEX |
