Folic acid, or vitamin B-9, received its name from one of its richest natural sources: foliage. Spinach, kale, beet greens and similar leafy greens are among the best places to find folic acid, or folate. Like other B vitamins, folate is water-soluble, but unlike most B vitamins it can be stored in your body for several months. It is easily destroyed by heat, light, acid and most methods of food processing. A lack of fresh, unprocessed foods in your diet could lead to folic acid deficiency.
Functions
Once folate enters your body, it is converted to its active form, tetrahydrofolic acid. THFA participates with vitamin B-12 in the production of hemoglobin, which is the oxygen-carrying protein in your red blood cells. In concert with vitamins C and B-12, THFA assists in the metabolism of proteins and amino acids. One of folic acid's most important roles is in the synthesis of DNA and RNA, which are needed for the growth, function and reproduction of all cells, particularly those that are dividing rapidly.
Deficiency is Common
"The Merck Manual of Diagnosis and Therapy" reports that folate deficiency is common. Inadequate intake, poor absorption and some medications, such as phenytoin, birth control pills or methotrexate, can lead to folate deficiency. The Linus Pauling Institute reports that conditions requiring rapid cell division, such as pregnancy or cancer, increase your body's need for folate. Bowel disorders, such as Crohn's disease or celiac disease, decrease folate assimilation. In most cases, however, folate deficiency results from insufficient consumption of folate-rich foods.
Signs and Symptoms of Folate Deficiency
Many symptoms of folic acid deficiency are nonspecific such as fatigue, light-headedness, weight loss, headache, diarrhea, irritability and depression could all be attributed to other causes. Glossitis, a painful inflammation of the tongue, sometimes occurs. The classic sign of folate deficiency is megaloblastic anemia, which is characterized by the production of fewer but abnormally large red blood cells. Some of your white blood cells also exhibit characteristic changes that can be identified under a microscope. During pregnancy, folate deficiency interferes with normal development of the fetal brain and spinal cord, leading to neural tube defects.
Considerations and Recommendations
Even though many foods are fortified with folate, deficiency is relatively common. Pregnant women are particularly at risk, due to daily needs that are markedly higher than those for the non-pregnant state. Because neural tube defects occur in the fourth week of pregnancy when many women do not yet realize they are pregnant, the National Academy of Sciences recommends that all women who are capable of becoming pregnant take at least 400 mcg of folate each day and increase the dosage to 600 mcg once pregnancy is discovered. Recommended daily allowances vary significantly with age and pregnancy status, ranging from 65 mcg for infants to 600 mcg for pregnant women.
References
- "Staying Healthy with Nutrition: Folic Acid (Folacin or Folate); Elson M. Haas, M.D.; 2006
- "The Merck Manual of Diagnosis and Therapy, 18th Edition: Folate"; Mark H. Beers, M.D., Editor-in-Chief; 2006
- The Linus Pauling Institute Micronutrient Information Center: Folic Acid
- The National Academies Press: Folate
Member Comments