Folate is a water soluble vitamin and one of the B vitamins. Folic acid is the form of folate found in most supplements and used in enrichment and fortification of foods.
The RDA for folate for adult men and women aged 19 and older is 400 micrograms a day and 600 micrograms a day for pregnant women. Ready to eat cereals, bread, and other grain products are the primary sources of folate in the US. Other good food sources are liver, spinach, lentils, oatmeal, asparagus, and romaine lettuce. Losses of folate can occur when food is heated or when folate leaches out of cooked foods and the liquid is thrown out.
A folate deficiency can cause many different health effects including macrocytic anemia. Folate and vitamin B12 deficiencies cause elevated levels of homocysteine in the blood. When folate intake is not adequate during pregnancy, neural tube defects can occur.
Source: Thompson, Janice, Melinda Manore, and Linda A. Vaughan. The Science of Nutrition. San Francisco, CA: Pearson Benjamin Cummings, 2011. Print.