Folate (Latin folium "leaf") is a B vitamin which occurs naturally in food. (Folic acid is the synthetic form.) Folate is needed to make DNA and RNA, the building blocks of cells. Adults and children need folate to make normal red blood cells and to prevent anemia. Folic acid can also correct the anemia associated with vitamin B12 deficiency but will not correct changes in the nervous system that result from vitamin B12 deficiency.
Leafy greens such as spinach and turnip greens, dry beans and peas, citrus fruits are rich food sources of folate. In 1996, the Food and Drug Administration published regulations requiring the addition of folic acid to enriched breads, cereals, flours, corn meals, pastas, rice, and other grain products to reduce the risk of birth defects in newborns.
Anti-convulsant medications, metformin (a medication to control blood sugar, sulfasalazine (used in Crohn's disease and ulcerative colitis), triamterene (a diuretic), and methotrexate can interfere with folate utilization.
A deficiency of folate may increase levels of homocysteine, an amino acid normally found in the blood. An elevated homocysteine level is an independent risk factor for heart disease and stroke. Several studies have associated diets low in folate with increased risk of breast, pancreatic, and colon cancer.