The Benefits of Vitamin B9 (folic acid)
By: Dr. Obikoya
Vitamin B9 also called Pteroylglutamic Acid, Folate, or
Folacin, is a vitamin of the B complex group that is essential for the metabolic
processes going on in our body. In humans, folic acid is necessary for the
synthesis of nucleic acids and the formation of heme, the pigmented,
iron-carrying component of the hemoglobin in red blood cells. A deficient intake
of folic acid can impair the maturation of young red blood cells, resulting in
folic-acid-deficiency anemia.
Folic acid essential for efficient neural tube development during pregnancy
which forms the brain and spinal cord. Pregnant women with an insufficient
intake of folic acid are more likely to give birth prematurely or to deliver
babies with low birth weight or with neural tube defects. The sulfa drugs are
thought to achieve their antimicrobial effects by interfering with the
production of folic acid within bacteria.
‘Neural tube defects’, such as spina bifida, in babies appear to be linked
to a ‘metabolic defect’ in folate metabolism in the mother. This means that,
even though the mother may have an adequate dietary intake of folic acid, her
body cannot use it efficiently.
Taking extra folic acid at the time when the neural tube is forming can reduce
the chance of the baby having a neural tube defect. However, the neural tube is
formed very early during pregnancy - about a month after conception.
Between the 17th and 30th day after conception (or 4 to 6 weeks after the first
day of a woman’s last menstrual period), the neural tube forms in the embryo
(developing baby) and then closes. The neural tube later becomes the baby’s
spinal cord, spine, brain, and skull.
A neural tube defect (NTD) occurs when the neural tube fails to close properly,
leaving the developing brain or spinal cord exposed to the amniotic fluid. The
two most common neural tube defects are anencephaly and spina bifida. Spina
bifida and anencephaly are birth defects that occur in the first four weeks of
pregnancy, before most women know that they are pregnant. Because about half of
all pregnancies are unplanned, it is important to include 400 micrograms of
folic acid in every childbearing age woman’s diet.
Women are advised to take folic acid prior to conception and to continue taking
folic acid supplements until the 12th week of pregnancy. In addition, folic acid
is essential for the formation of red blood cells and has been shown to reduce
the levels of an amino acid (homocysteine). This reduction may have a protective
effect against heart disease.
The recommended amount of folic acid to prevent spina bifida and other neural
tube defects is 400 micrograms (0.4 milligram) of synthetic folic acid daily.
This can be consumed in Two ways: Take a multivitamin with 400 micrograms (0.4
mg) of folic acid or take single pill of 400 mcg of folic acid every day. Folic
acid pills are small and easy to swallow.
Folic acid has no known toxic level. If you were to eat a bowl of fully
fortified cereal ( 400 micrograms), take 400 micrograms (0.4 milligram) folic
acid supplement, and eat fortified foods and foods rich in folate, women of
reproductive age would not have a problem with too much folic acid.
Even in very high amounts folic acid is non-toxic. Nevertheless, it is
recommended that women consume no more than 1,000 micrograms of synthetic folic
acid a day. Large amounts of folic acid may hide the ability to quickly diagnose
a rare vitamin B-12 deficiency, pernicious anemia.
This condition primarily affects the elderly population and, in some cases, can
lead to neurological damage. Today, doctors can use a simple definitive test to
check for a B-12 deficiency.
We all need folic acid supplements. Older people (over 55) and those who consume
large amounts of alcohol need to take even more folic acid supplements.
High levels of the amino acid homocysteine are independently associated with an
increased risk of heart disease and stroke. It has been shown that taking folic
acid lowers homocysteine levels in both men and women, but it is not yet known
whether folic acid supplementation also lowers the risk of heart disease and
stroke.
There are some indications that folic acid use may also reduce the risk for
other birth defects, such as cleft lip and palate and certain congenital heart
defects.
Folic acid may also play a role in protecting against some forms of cancer and
heart disease. Decreased blood levels of folic acid are associated with an
increased risk of colon cancer in women.1 Long-term supplementation with folic
acid from a multivitamin has been found in one large population study to be
associated with a reduced risk of colon cancer. However, 15 years of
supplementation was necessary before a significant reduction in colon-cancer
risk became apparent. In that study, folic acid from dietary sources alone was
associated with a modest reduction in the risk of colon cancer.2
References
1. Kato I, Dnistrian AM, Schwartz M, et al. Serum folate, homocysteine and
colorectal cancer risk in women: a nested case-control study. Br J Cancer
1999;79:1917-21.
2. Giovannucci E, Stampfer MJ, Colditz GA, et al. Multivitamin use, folate and
colon cancer in women in the Nurse’s Health Study. Ann Intern Med
1998;129:517-24.