Folic Acid Also known as: folate What does it do? Folic acid is needed for DNA synthesis. DNA allows cells including cells in the fetus when a woman is pregnant to replicate normally. Adequate intake of folic acid early in pregnancy is important for preventing most neural tube birth defects1 and may also protect against some birth defects of the arms, legs, and heart.2 It also appears to protect against cleft palate and cleft lip formation in most,3 4 though not all,5 studies. Folic acid is needed to make SAMe (S-adenosyl-Lmethionine), which affects (and may improve) mood. Folic acid is also needed to keep homocysteine (an amino acid) levels in blood from rising. Excess homocysteine has been linked to an increased risk of heart disease in most studies and may also be linked to osteoporosis, strokes, and Alzheimer s disease. Where is it found? Beans, leafy green vegetables, citrus fruits, beets, wheat germ, and meat are good sources of folic acid. Folic acid has been used in connection with the following conditions (refer to the individual health concern for complete information):
Primary:Celiac disease (if deficient), Crohn s disease, Depression, Gingivitis (periodontal disease) (rinse only), High homocysteine, Pap smear (abnormal), Pregnancy and postpartum support. Secondary: Atherosclerosis, Ulcerative colitis. Other: Alzheimer s disease, Diarrhea, Gout, High cholesterol (protection of LDL cholesterol), HIV support, Osteoporosis, Restless legs syndrome, Vitiligo. Who is likely to be deficient? Most people do not consume the recommended amount of folic acid. Recently, scientists have found that many people with heart disease have elevated blood levels of homocysteine, which is often controllable with folic acid. This suggests that many people in Western societies have a mild folic acid deficiency. In fact, increasing folic acid intake could potentially prevent an estimated 13,500 deaths from cardiovascular diseases each year.6 Folic acid deficiency is also common in alcoholics, people living at poverty level, those with malabsorption disorders, and women taking the birth control pill. Recently, elderly people with hearing loss have been reported to be much more likely to be folic acid deficient than healthy elderly individuals.7 How much is usually taken? All women who are or who could become pregnant should take 400 800 mcg per day in order to reduce the risk of birth defects. Many nutritionally oriented doctors recommend 400 mcg to others. Dietary folate is much less available to the body compared with
synthetic folic acid found in most supplements. Therefore adding supplemental folic acid from a vitamin pill is probably important. Are there any side effects or interactions? Folic acid is not generally associated with side effects.8 However, folic acid supplementation can interfere with the laboratory diagnosis of vitamin B12 deficiency, possibly allowing the deficiency to progress undetected to the point of irreversible nerve damage.9 Although vitamin B12 deficiency is uncommon, no one should supplement with 1,000 mcg or more of folic acid without consulting a nutritionally oriented doctor. Vitamin B12 deficiencies often occur without anemia (even in people who don t take folic acid supplements). Some doctors do not know that the absence of anemia does not rule out a B12 deficiency. If this confusion delays diagnosis of a vitamin B12 deficiency, the patient could be injured, sometimes permanently. This problem is rare and should not happen with doctors knowledgeable in this area using correct testing procedures. Folic acid is needed by the body to utilize vitamin B12. Proteolytic enzymes and antacids10 inhibit folic acid absorption.11 People taking either of these are advised to supplement with folic acid. Folic acid-containing supplements may interfere with methotrexate therapy in people with cancer. People using methotrexate for cancer treatment should ask their
prescribing doctor before using any folic acid-containing supplements. Until recently, methotrexate was believed to help people with rheumatoid arthritis also by interfering with folic acid metabolism. However, recent research has shown that this is not so. In fact, people with rheumatoid arthritis taking methotrexate should supplement large amounts of folic acid. The same now appears to be true for people with severe psoriatic arthritis who are taking methotrexate. However, high levels of folic acid should not be taken without clinical supervision. References: 1. Daly LE, Kirke PN, Molloy A, et al. Folate levels and neural tube defects. JAMA 1995;274:1698 1702. 2. Shaw GM, O Malley CD, Wasserman CR, et al. Maternal periconceptional use of multivitamins and reduced risk for conotruncal heart defects and limb deficiencies among offspring. Am J Med Genetics 1995;59:536 45. 3. Tolarova M. Periconceptional supplementation with vitamins and folic acid to prevent recurrence of cleft lip. Lancet 1982;ii:217 [letter]. 4. Shaw GM, Lammer EJ, Wasserman CR, et al. Risks of orofacial clefts in children born to women using multivitamins containing folic acid periconceptionially. Lancet 1995;345:393 96. 5. Hayes C, Werler MM, Willett WC, Mitchell AA. Case-control study of periconceptional folic acid supplementation and oral clefts. Am J Epidemiol 1996;143:1229 34. 6. Russel RM. A minimum of 13,500 deaths annually from coronary artery disease could be prevented by increasing folate intake to reduce homocysteine levels. JAMA 1996;275:1828 29. 7. Houston DK, Johnson MA, Nozza RJ, et al. Age-related hearing loss, vitamin B-12, and folate in elderly women. Am J Clin Nutr 1999;69:564 71. 8. Butterworth CE Jr, Tamura T. Folic acid safety and toxicity: a brief review. Am J Clin Nutr 1989;50:353 58. 9. Wald NJ, Bower C. Folic acid, pernicious anaemia, and prevention of neural tube defects. Lancet 1994;343:307.
10. Russell RM, Golner BB, Krasinski SD, et al. Effect of antacid and H2 receptor antagonists on the intestinal absorption of folic acid. J Lab Clin Med 1988;112:458 63. 11. Russell RM, Dutta SK, Oaks EV, et al. Impairment of folic acid absorption by oral pancreatic extracts. Dig Dis Sci 1980;25:369 73. ------------------------------------------------------------------------