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Folic Acid, a synthetic form of Folate, is a B vitamin found in a variety
of foods and added to many vitamin and mineral supplements. Folate is
needed both before and in the first weeks of pregnancy and can help
reduce the risk of certain serious and common birth defects called neural
tube defects, which affect the brain and spinal cord.
The tricky part is that neural tube defects can occur in an embryo
before a woman realizes she's pregnant. That's why it's important for
all women of childbearing age (15 to 45) to include folate in their
diets: If they get pregnant, it reduces the chance of the baby having
a birth defect of the brain or spinal cord.
"Adequate folate should be eaten daily and throughout the childbearing
years," said Elizabeth Yetley, Ph.D., a registered dietitian and
director of FDA's Office of Special Nutritionals.
Folate's potential to reduce the risk of neural tube defects is so
important that the Food and Drug Administration requires food manufacturers
to fortify enriched grain products with folic acid. This will give women
one way to get sufficient folate: by eating fortified breads and other
grain products, such as enriched pasta, rice, waffles and cereal bars.
Other ways to do this are:
- Eat fruits, dark-green leafy vegetables, dried beans and peas, and
other foods that are natural sources of folate.
- Eat folic acid-fortified enriched cereal grain products and breakfast
cereals.
- Take a vitamin supplement containing folic acid.
Nutrition information on food and dietary supplement labels can help
women determine whether they are getting enough folate, which is 400
micrograms (0.4 milligrams) a day before pregnancy and 800 micrograms
a day during pregnancy.
Neural Tube Birth Defects
The technical names of the two major neural tube birth defects reduced
by adequate folate intake are anencephaly and spina bifida. Babies with
anencephaly do not develop a brain and are stillborn or die shortly
after birth. Those with spina bifida have a defect of the spinal column
that can result in varying degrees of handicap, from mild and hardly
noticeable cases of scoliosis (a sideways bending of the spine) to paralysis
and bladder or bowel incontinence. With proper medical treatment, most
babies born with spina bifida can survive to adulthood. But they may
require leg braces, crutches, and other devices to help them walk, and
they may have learning disabilities. About 30 percent have slight to
severe mental retardation.
The national Centers for Disease Control and Prevention estimate that
about 2,500 infants with spina bifida and anencephaly are born each
year in the United States.
Other maternal factors also may contribute to the development of neural
tube defects. These include:
- family history of neural tube defects
- prior neural tube defect-affected pregnancy
- use of certain antiseizure medications
- severe overweight
- hot tub use in early pregnancy
- fever during early pregnancy
- diabetes.
Any woman concerned about these factors should consult her doctor.
Folate Link
Scientists first suggested a link between neural tube birth defects
and diet in the 1950s. The incidence of these conditions has always
been higher in low socioeconomic groups in which women may have poorer
diets. Also, babies conceived in the winter and early spring are more
likely to be born with spina bifida, perhaps because the mother's diet
lacks fresh fruits and vegetables--which are good sources of folate--during
the early weeks of pregnancy.
In 1991, British researchers found that 72 percent of women who had
one pregnancy with a neural tube birth defect had a lower risk of having
another child with this birth defect when they took prescription doses
of folic acid before and during early pregnancy.
Another study looked at folic acid intake in Hungarian women. The
evidence indicated that mothers who had never given birth to babies
with neural tube defects and who took a multivitamin and mineral supplement
with folic acid had less risk in subsequent pregnancies for having babies
with neural tube defects than women given a placebo.
These studies led the U.S. Public Health Service in September 1992
to recommend that all women of childbearing age capable of becoming
pregnant consume 0.4 mg of folate daily to reduce their risk of having
a pregnancy affected with spina bifida or other neural tube defects.
That corresponds to FDA's Daily Value for folic acid, which is 400
micrograms for nonpregnant women, as well as children 4 and older and
adult men. For pregnant women, the Daily Value jumps to 800 micrograms.
Daily Values are dietary reference numbers used on the Nutrition Facts
panel on food labels to show the amounts of various nutrients in a serving
of food.
Many women between 19 and 50 consume much less than 400 micrograms
of folate a day, according to the U.S. Department of Agriculture.
Sources of Folate
Folate occurs naturally in a variety of foods, including liver; dark-green
leafy vegetables such as collards, turnip greens, and Romaine lettuce;
broccoli and asparagus; citrus fruits and juices; whole-grain products;
wheat germ; and dried beans and peas, such as pinto, navy and lima beans,
and chickpeas and black-eyed peas.
Under FDA's folic acid fortification program, which became effective
January 1998, the agency requires manufacturers to add from 0.43 mg
to 1.4 mg of folic acid per pound of product to enriched flour, bread,
rolls and buns, farina, corn grits, cornmeal, rice, and noodle products.
A serving of each product will provide about 10 percent of the Daily
Value for folic acid. Whole-grain products do not have to be enriched
because they contain natural folate. Some of the natural folate in non-whole-grain
products is lost in the process of refining whole grains.
Folate also can be obtained from dietary supplements, such as folic
acid tablets and multivitamins with folic acid, and from fortified breakfast
cereals.
A report recently released by the Institute of Medicine indicates
that the evidence suggests that folic acid, the synthetic form of folate,
may be better absorbed than folate found naturally in foods. The report
also points out that, if taken in adequate amounts, food folate may
eventually be demonstrated to be as effective as folic acid.
Foods Containing Folate
| Food |
Serving Size |
Amount (Micrograms) |
%Daily Value* |
| Chicken liver |
3.5 oz |
770 |
193 |
| Breakfast cereals |
1/2 to 1 1/2 cup |
100 to 400 |
25 to 100 |
| Braised beef liver |
3.5 oz |
217 |
54 |
| Lentils, cooked |
1/2 cup |
180 |
45 |
| Chickpeas |
1/2 cup |
141 |
35 |
| Asparagus |
1/2 cup |
132 |
33 |
| Spinach, cooked |
1/2 cup |
131 |
33 |
| Black beans |
1/2 cup |
128 |
32 |
| Burrito with beans |
2 |
118 |
30 |
| Pasta |
2 oz. |
100-120 |
25-30 |
| Kidney beans |
1/2 cup |
115 |
29 |
| Cereal bars |
1 bar |
40-100 |
10-25 |
| Baked beans with pork |
1 cup |
92 |
23 |
| Lima beans |
1/2 cup |
78 |
20 |
| White rice, cooked |
3/4 cup |
60 |
15 |
| Tomato juice |
1 cup |
48 |
12 |
| Brussels sprouts |
1/2 cup |
47 |
12 |
| Orange |
1 medium |
47 |
12 |
| Broccoli, cooked |
1/2 cup |
39 |
10 |
| Fast-food French fries |
large order |
38 |
10 |
| Wheat germ |
2 tbsp |
38 |
10 |
| Fortified white bread |
1 slice |
38 |
10 |
* based on Daily Value for folate of 400 micrograms
(Source: Food Values of Portions Commonly Used, 16th edition)
How to Find Foods Containing Folate or Folic Acid
Certain information on food and dietary supplement labels can help
women spot foods containing substantial amounts of folate. Some labels
may claim that the product is "high in folate or folic acid,"
which means a serving of the food provides 20 percent or more of the
Daily Value for folic acid. Or the label may say the food is a "good
source" of folate, which means a serving of the food provides 10
to 19 percent of the Daily Value for folic acid. The exact amount will
be given in the label's Nutrition Facts panel.
Some food and dietary supplement labels may carry a longer claim that
says adequate folate intake may reduce the risk of neural tube birth
defects. Products carrying this claim must:
- provide 10 percent or more of the Daily Value for folic acid per
serving
- not contain more than 100 percent of the Daily Value for vitamins
A and D per serving because high intakes of these vitamins are associated
with other birth defects
- carry a caution on the label about excess folic acid intake, if
a serving of food provides more than 100 percent of the Daily Value
for folic acid. FDA has set 1 mg (or 1,000 micrograms) of folate daily
as the maximum safe level. There are limited data on the safety of
consuming more than 1 mg daily, and there may be a risk for people
with low amounts of vitamin B12 in their bodies--for example,
older people with malabsorption problems, and people on certain anticancer
drugs or drugs for epilepsy whose effectiveness can diminish when
taken with high intakes of folate.
- list on the label's Nutrition or Supplement Facts panel the amount
by weight in micrograms and the %Daily Value of folate per serving
of the product. This information, which appears toward the bottom
of the panel, along with the listing of other vitamins and minerals,
can be used to compare folate levels in various foods and supplements.
Optional information may appear with the health claim to let consumers
know about other risks associated with neural tube birth defects, when
to consult a doctor, other foods that are good sources of folate, and
other important messages about neural tube defects.
More Considerations
The claim about folate cannot imply that adequate folate intake alone
will ensure a healthy baby, since so many factors can affect a pregnancy.
Women should bear this in mind when contemplating pregnancy, advises
Jeanne Latham, a registered dietitian and consumer safety officer in
FDA's Office of Special Nutritionals. "Folate can make a significant
contribution," she said, "many factors, including an overall
good diet, are involved in having a healthy baby."
Genetics plays a role, as do other healthful prenatal practices, such
as eating an all-around good diet. But unlike genetics, diet is a risk
factor women can modify to their--and their baby's--advantage, said
Jeanne Rader, Ph.D., director of the division of science and applied
technology in FDA's Office of Food Labeling.
"Folic acid is one of many nutrients needed in a healthy diet
for women of childbearing age," she said. "A well-balanced
diet with a variety of foods can provide all those nutrients, including
adequate amounts of folate."
Women have options for reaching the folate intake goal: They can get
the necessary nutrients and calories both before and during pregnancy
by eating a well-balanced diet, keeping in mind folate-rich foods, nutrition
experts say. Folic acid-fortified grain products, including breakfast
cereals, will help, too. Dietary supplements are another source of folate.
Any one or a combination of these options for ensuring adequate folate
can help assure women of childbearing age that, if they become pregnant,
their babies will be off to a healthy start.
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