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What Is It
This water-soluble B vitamin, also called folacin or folate,
was first identified in the 1940s when it was extracted from
spinach. Because the body can't store it very long, you need
to replenish your supply daily. Cooking, or even long storage,
can destroy up to half the folic acid in foods, so supplements
may be the best way to get enough of this vital nutrient.
What Does It Do
In the body, folic acid is utilized thousands of times a day
to make blood cells, heal wounds, build muscle; in fact, it's
necessary for every function that requires cell division.
Folic acid is critical to DNA and RNA formation and assures
that cells duplicate normally. It is especially important
in fetal development and helps produce key chemicals for the
brain and nervous system.
Common Uses
• Protects against birth defects.
• Reduces heart disease and stroke risk.
• Lowers risk for several cancers.
Prevention
Adequate folic acid at conception and for the first three
months of pregnancy greatly reduces the risk of serious birth
defects, including spina bifida. This B vitamin also appears
to regulate the body's production and use of homocysteine,
an amino acid-like substance that at high levels may damage
the lining of blood vessels, making them more susceptible
to plaque buildup. This makes folic acid an important weapon
against heart disease. In addition, it may be useful in warding
off certain cancers, including those of the lungs, cervix,
colon, and rectum.
Additional Benefits
Folic acid may help depression. Because high levels of homocysteine
may contribute to this condition, some experts think folic
acid (which is often deficient in people who are depressed)
may be of value because it reduces homocysteine levels. Studies
also show that taking folic acid improves the effectiveness
of antidepressants in people with low folic acid levels. Folic
acid supplements have been useful in treating gout and irritable
bowel syndrome as well. Because high homocysteine levels may
be a factor in osteoporosis, folic acid may even help keep
bones strong.
How Much You Need
The current adult RDA for folic acid is 400 mcg a day.Supplements
are important for older people, who may not get enough of
this vitamin in food.
If You Get Too Little: Though relatively
rare, a severe folic acid deficiency can cause a form of anemia
(megaloblastic anemia), a sore red tongue, chronic diarrhea,
and poor growth (in children). Alcoholics and people who are
on certain medications (for cancer or epilepsy) or who have
malabsorption diseases (Crohn's, celiac sprue) are susceptible
to severe deficiency. Much more common is a low level of folic
acid, which causes no symptoms but raises the risk of heart
disease or birth defects.
If You Get Too Much: Very large doses (5,000
to 10,000 mcg) offer no benefit and may be dangerous for people
with hormone-related cancers, such as those of the breast
or prostate. High doses may also cause seizures in those with
epilepsy. The National Academy of Sciences suggest an upper
daily limit for folic acid of 1,000 mcg for adults.
How To Take It
Dosage: For overall good health and the prevention
of heart disease: Take a dose of 400 to 800 mcg of folic acid
a day. For women who might become pregnant: Take a total of
800 mcg a day. (Adequate folic acid stores are important because
the vitamin plays a role in a baby’s development from
conception.) For people with depression: Take 400 mcg a day,
as part of vitamin B-complex supplement.
Guidelines For Use: Folic acid can be taken
at any time of the day, with or without food. When taking
individual folic acid supplements for any reason, combine
it with an additional 1,000 mcg of vitamin B12 to prevent
a B12 deficiency.
Other Sources
Excellent food sources of folic acid include green vegetables,
beans, whole grains, and orange juice. Some refined grain
products are now fortified with folic acid.
Latest Findings
• For prevention of disease, the best way to get enough
folic acid may be through supplements. In a small study, people
taking 400 mcg of folic acid a day in pills or in specially
fortified foods increased their folic acid level. But those
who just ate foods naturally rich in folic acid showed no
increase. Scientists speculate that the folic acid found naturally
in foods may not be absorbed well enough to have a therapeutic
effect.
• A preliminary study from Oxford University hints that
folic acid may play a role in preventing Alzheimer's disease.
People with the disease tended to have lower blood levels
of folic acid and vitamin B12 than healthy people of the same
age.
Caution!
Folic acid supplements, even at normal doses, may mask a type
of anemia caused by a vitamin B12 deficiency. Unchecked, this
anemia can cause irreversible nerve damage and dementia. If
you take folic acid supplements, be sure to take extra vitamin
B12 as well.
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