Experts Debate on Folic Acid: How Much Is Enough?
Folic acid fortification of foods, mandated since 1998 in the US, continues to help reduce the incidence of severe birth defects such as spina bifida, according to a study reported in the journal Pediatrics.
The study included a look at the effects of folic acid, a B vitamin, on children born to African-American and Hispanic women.
"We wanted to see if all racial and ethnic groups are having decreases, or is it only, for example, in one group?" explains study co-author Dr. Sonja Rasmussen, a clinical geneticist with the Centers for Disease Control and Prevention (CDC).
The CDC team concluded that folic acid fortification accounted for a 36 percent decline in the birth defects among the Hispanic population, and a 34 percent decline in the non-Hispanic Caucasian population. The decline among African-American women was not significant.
Before fortification, about 4,000 pregnancies annually were affected by neural tube defects, according to the March of Dimes. Now, about 1,000 fewer babies a year develop one of these conditions.
Dr. Rasmussen's team analyzed data from 21 population-based birth defect surveillance systems.
They examined trends in neural tube defects - serious malformations such as spina bifida, a leading cause of childhood paralysis, and anencephaly, a condition in which parts of the brain and skull cap are missing.
Both can be prevented through maternal intake of folate during pregnancy. Folate is thought to be important to embryonic development. Folate is a form of folic acid that occurs naturally in foods such as leafy green vegetables, citrus fruits, and dried beans and peas.
Looking at the years 1995 to 2002, the team divided births into pre-fortification, optional- and mandatory-fortification periods, and then evaluated associations between maternal folate levels and birth defects.
The study included data on 4,468 cases of spina bifida and 2,625 cases of anencephaly.
But some experts believe the fortification level, while helpful, needs to be set higher.
In an editorial accompanying the study, Dr. Godfrey Oakley, Jr. of the CDC says the US Food and Drug Administration should at least double the amount of folic acid required in enriched grain foods, currently set at 140 micrograms per 100 grams of grains.
The March of Dimes is also calling for higher fortification levels, says Dr. Jennifer Howse, president of the organization. She calls the decline found in the Dr. Rasmussen study "very significant," but thinks higher levels of fortification are needed.
In a note of caution, however, Dr. Tsunenobu Tamura, author of a second Pediatrics study on folate status and child development, said more study is needed before that recommendation should be enacted.
"We should be extremely careful in increasing the fortification level because we do not know the consequences of high-dose fortification," says Dr. Tamura, a professor of nutrition science at the University of Alabama at Birmingham.
In his study, Dr. Tamura's team evaluated the maternal blood folate levels of African-American women at 19, 26, and 37 weeks of pregnancy. They then evaluated the neurological development of 355 of the women's children at five years of age using memory, motor skills, and other tests.
"The mothers' folate nutritional status during pregnancy does not appear to affect psychomotor development of the children at five years of age," he says.
Still, he notes, he believes it is crucial that women get adequate folate during pregnancy.
Women of childbearing age are advised to take in 400 micrograms a day of folate, which can be obtained through vitamin pills or foods such as leafy green vegetables and citrus fruits.
Always consult your physician for more information.
|
Folic acid is a naturally occurring B vitamin that helps a baby's neural tube, the part of a developing baby that becomes the brain and spinal cord, develop properly, according to the March of Dimes.
Folic acid must be taken before and during early pregnancy when the neural tube is developing.
The best way to get enough folic acid is to take a multivitamin with 400 micrograms of folic acid in it and eat a healthy diet, states the March of Dimes. Most multivitamins have this amount, but one should check the label to be sure.
Folic acid can be found in the diet, but it is hard to get enough every day through food alone. That is why the March of Dimes encourages all women of childbearing age to take a multivitamin containing folic acid every day as part of a healthy diet.
Folic acid works, but it only works if taken before and during the first few weeks of pregnancy, when the neural tube is developing into the brain and spinal cord.
When the neural tube does not close properly, a baby is born with a very serious birth defect called a neural tube defect.
About 2,500 children are born each year in the US with a neural tube defect. If all women took adequate folic acid before conception and during pregnancy, the number of babies born with a neural tube defect could drop by as much as 70 percent, estimates the March of Dimes.
Folic acid has no known toxic level. If a woman eats a bowl of fully fortified cereal (400 micrograms), took a folic acid supplement (400 micrograms), and ate fortified foods and foods rich in folate, experts say this would not be too much folic acid.
However, the CDC recommends that women consume no more than 1,000 micrograms of synthetic folic acid a day.
Folic acid is found in the following foods:
-
fortified breakfast cereals such as Total® and Product 19®
-
lentils
-
asparagus
-
spinach
-
black beans
-
peanuts (only if you do not have a peanut allergy)
-
orange juice (from concentrate is best)
-
enriched breads and pasta
-
romaine lettuce
-
broccoli
Always consult your physician for more information.
|
