Getting sufficient levels of dietary folate or taking folic acid supplements is especially important for women who may become pregnant. Folate deficiency have been correlated with increased risk of a spinal cord birth defect called Spina Bifida. This defect can occur very early in pregnancy so it is important that moms-to-be start folic acid supplementation or eat folate-rich foods early, even before they attempt to get pregnant.
Folate is found in citrus fruits, green leafy vegetables, and whole grains. Women who might become pregnant should take a 800 mcg folic acid supplement each day to prevent neural tube defects such as spina bifida.
Since folic acid will reduce levels of homocysteine, many people take folic acid supplements with the hope that lower homocysteine levels will help to reduce the risk of heart disease and some cancers. Folic acid supplements are very safe, but if you are interested in taking large amounts, over 1000 mcg per day, you should seek the advice of a health care professional who is trained in therapeutic nutrition. Sources: Wald D, Morris J,
Law M, Wald N. "Folic Acid, homocysteine, and cardiovascular disease: judging causality in the face inconclusive trial events." BMJ 2006 November; 333: 1114-1117.
Martinez de Villarreal LE, Arredondo P, Hernandez R, Villarreal JZ. "Weekly administration of folic acid and epidemiology of neural tube defects." Matern Child Health J. 2006 Sep;10(5):397-401.


