Folic Acid and Prenatal / Preconception Vitamins

Folic acid (also known as vitamin B₉ or folacin) and folate (the naturally occurring form) is an important nutrient for women who may become pregnant, because a women’s blood levels of folate fall during pregnancy due to an increased maternal RBC synthesis in the fist half of the pregnancy and fetal demands in the second half. The first four weeks of pregnancy (when most women do not even realize they are pregnant) require folic acid for proper development of the brain, skull, and spinal cord. Serious birth defects like neural tube defects are less likely to occur when women take 0.4 mg of folic acid daily. Adequate folate intake during the periconceptional period, the time right before and just after a woman becomes pregnant, helps protect against a number of congenital malformations.

Folate in foods and other sources

Leafy vegetables such as spinach, asparagus, turnip greens, romaine lettuces, dried or fresh beans and peas, fortified grain products (pasta, cereal, bread), sunflower seeds and certain other fruits (orange juice, canned pineapple juice, cantaloupe, honeydew melon, grapefruit juice, banana, raspberry, grapefruit, strawberry) and vegetables (beets, broccoli, corn, tomato juice, vegetable juice, brussels sprouts, bok choy) are rich sources of folate.

Liver and liver products also contain high amounts of folate, as does baker’s yeast. Some breakfast cereals (ready-to-eat and others) are fortified with 25% to 100% of the recommended dietary allowance (RDA) for folic acid. Folic acid is added to grain products in many countries, and in these countries fortified products make up a significant source of the population’s folic acid intake.

Folic acid naturally found in food is susceptible to high heat, UV, and is soluble in water. It is heat labile in acidic environments and may also be subject to oxidation.

Some meal replacement products do not meet the folate requirements as specified by the RDAs.

What is the recommended folic acid intake before and during pregnancy?

The U.S. Public Health Service recommends that women of childbearing age get at least 400 micrograms of folic acid each day, through food sources and/or supplements. For women who are thinking about getting pregnant, health care providers recommend supplementing the diet with folic acid for three months before pregnancy, and then for at least the first three months of pregnancy. Prenatal vitamins are a good way to get extra folic acid into the diet.

Are prenatal supplements necessary?

Definitely, yes! Prenatal supplements often contain high amounts of folic acid and other compounds, such as iron and vitamin A. (But, women should take care in choosing a supplement, to make sure that no more than 5,000 IU of vitamin A is included.) Findings from research supported by the NICHD and other agencies indicate that the right amount of folic acid can help prevent certain types of birth defects and other problems during pregnancy.

Even though many foods available in the United States are fortified with folic acid, women who are thinking about pregnancy benefit from an extra boost of this important compound. It can be hard to get the full amount of folic acid from food sources alone, so preconception supplements are important.