Folic Acid Essential for All Women of Childbearing Age
November 22, 1999
It's been known for some time that folic acid prevents birth defects, but researchers from the University of Nebraska Medical Center have completed research that helps to explain exactly how this occurs.
Building on previous research that identified a special receptor (folate-binding protein or Folbp1) that helps to bring folic acid into the cell, researchers genetically engineered mice that lacked Folbpl. In addition, they also genetically engineered a group of mice that lacked another receptor for folic acid, Folbp2.
The mice embryos without Folbp2 developed normally, but the mice embryos without Folph1 died while still in the uterus. When pregnant Folph1-deficient mice were given large amounts of folic acid, their offspring developed normally--despite being genetically programmed to lack the folate receptor. It seems that high doses of folic acid somehow overrode the genetic defects that caused the developing mice embryos to perish.
At present, researchers believe that the corresponding genetic defect in women is also somehow "corrected" by large infusions of folic acid. The present daily folic acid recommendation for pregnant women is 1000 micrograms (mcg), which is equal to one milligram. For everyone else, the recommended dose is 400 mcg every day.
The most severe birth defects associated with folic acid deficiency involve the neural tube. The neural tube is the embryonic precursor to the brain and the spinal cord. Since the neural tube develops so early in pregnancy, the damage can be done before a woman even realizes that she is pregnant. However, this can easily be avoided if every woman of childbearing age takes folic acid on a daily basis.
In addition to neural tube defects, folic acid deficiency has been linked to other birth defects as well, including cleft palate and cleft lip.