High concentrations of this vitamin were initially found in spinach - known in Latin as "folium". This gave rise to the common name, folic acid. In the body, folic acid plays an essential role in the synthesis of DNA and RNA and is also key in the formation of red blood cells, protein metabolism, reproduction and growth. Folic acid also assists in the formation of white blood cells and aids in strengthening the immune system. It is vital to a healthy nervous system, intestinal tract and normal patterns of growth. Folic acid is very important during pregnancy, as it helps to regulate embryonic and fetal nerve cell formation, which is vital for normal development.