Folate or folic acid (sometimes known as vitamin B9) is the form of a particular B vitamin found in foods. Folate is the generic term for all forms of this vitamin. Folic acid is the man-made or synthetic form of the vitamin. It is found in fortified foods and vitamin supplements.
In what food source is the nutrient found?
Foods naturally high in folate include:
- citrus fruits
- organ meats
- peanuts and other legumes
- spinach and other dark greens
- wheat germ
- yeast breads
Certain grain products have folic acid added to them and are good sources of the nutrient. These include commercial breads, cereals, and pastas. Items made from enriched flour products also supply folic acid. Enriched grain products must be fortified with folic acid.
Fortification is required so that women of childbearing age consume enough folate. Women who become pregnant and have not consumed enough folic acid are at risk of delivering a baby who has a neural tube defect (NTD). Neural tube defects are malformations in the unborn child that occur during pregnancy. The defects involve the skull and spinal column.
Researchers think that most Americans get between 220 and 280 mcg a day of folate from their diets. Since certain grain products have been fortified with folic acid, the incidence of neural tube defects in the U.S. has decreased by 19%. The RDA (Recommended Dietary Allowance) for folate is 400 mcg per day for adult men and women, including women of childbearing age.
If a woman is pregnant, the RDA is 600 mcg, and if breastfeeding, 500 mcg. This intake should be from fortified foods, supplements, or both. Folic acid has no known toxic level. However, daily intake of folic acid should not exceed 1,000 mcg. Too much folate can mask the symptoms of a vitamin B12 deficiency. The FDA restricts the amount of folic acid supplements to 400 mcg for adults. Supplements for pregnant women are restricted to 800 mcg.
How does the nutrient affect the body?
In the body, folate plays an important role in the following processes:
- formation of hemoglobin in red blood cells
- normal growth and maintenance of all cells
- prevention of neural tube defects in fetuses before birth
- production of neurotransmitters, such as serotonin, that regulate mood, sleep, and appetite
Getting enough folate during pregnancy lowers the risk of neural tube defects and cleft lip/palate in newborns by at least 50 percent. A neural tube defect occurs when the neural tube fails to close properly. The developing brain or spinal cord is exposed to the amniotic fluid in the woman's uterus.
The two most common neural tube defects are anencephaly and spina bifida. People with spina bifida have a defect of the spinal column that can result in varying degrees of disability. Babies with anencephaly do not develop a brain. They are stillborn or die shortly after birth.
Folate is crucial during the first 18 to 30 days of pregnancy. The baby's brain and spinal column are in a critical stage of development during this period. Because a woman may not even know that she is pregnant at this early stage, it is very important for all women of childbearing age to consume enough folate.
The Centers for Disease Control and Prevention (CDC) has estimated that in about 1 of every thousand pregnancies in the U.S., the unborn child is affected with spina bifida or anencephaly. If all women of childbearing age consumed 400 mcg of folate per day, it could result in a 2/3 decrease in this rate.
Folate may also have a role in lowering heart disease risk. Scientists are studying the link between folate and a substance called homocysteine. High homocysteine levels in the blood have been linked with a higher heart disease risk. Homocysteine levels seem to be lower in people who get plenty of folate in their diets.
Current evidence also suggests that folate may have a role in the prevention of some cancers. This is especially true when it is consumed along with a variety of nutrients found in fruits, vegetables, and other foods.
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