new study finds that the vitamin was no better than a placebo in preventing
If you take a daily supplement of B vitamins in the hopes of warding off a heart
attack, a new study confirms what previous findings have already suggested:
You're wasting your money.
In a review of eight trials involving 24,210 people, not one study supported the
notion that taking B vitamins prevents heart disease. When analyzed together,
the data showed that B vitamin pills were no better than placebos at guarding
against heart attack, stroke or death from heart disease.
The new study was led by Venezuelan researcher Arturo Marti-Carvajal of the
Cochrane Network, an international body that performs systematic reviews of
The idea that B vitamins – in particular folic acid, B6 and B12 – protect from
heart disease has to do with homocysteine, an amino acid found normally in the
blood. When elevated, however, homocysteine is thought to increase the risk of
heart attack and stroke.
Excess homocysteine impairs flow through blood vessels and makes it easier for
blood-clotting cells to clump together, which can lead to a heart attack.
Folic acid, B6 and B12 are needed to breakdown homocysteine and prevent it from
building up in the bloodstream.
your diet lacks these B vitamins, your homocysteine level can rise. One study
found that consuming too little folate increased the risk of cardiac events.
Folic acid, added to vitamin supplements and fortified foods, is the synthetic
version of the B vitamin folate.
Folate occurs naturally in such foods as leafy greens, asparagus, legumes,
avocado and citrus fruit.
Researchers have also demonstrated that supplementing with B vitamins,
especially folic acid, lowers elevated blood homocysteine.
Even so, there's no evidence that bringing down homocysteine prevents a future
heart attack or stroke. In fact, previous studies have found B vitamin
supplements ineffective for preventing heart attack, stroke or cardiac bypass
surgery in people with existing heart disease or those at high risk for
The current analysis of eight homocysteine-lowering trials concluded there's no
justification for taking B vitamins to keep your heart healthy.
It's unclear why B vitamins haven't helped. It's possible that since mandatory
folic acid food fortification – introduced in 1998 to reduce birth defects – B
vitamin supplements have a lesser effect on homocysteine levels than expected.
(In Canada, white flour, enriched pasta and enriched cornmeal are fortified with
folic acid.) Or B vitamins may have no effect on the course of heart disease.
Trials have been conducted in individuals at high risk for suffering a cardiac
event. The effect of taking folic acid on risk of heart disease in healthy
people is unknown.
There's another reason to consider pitching your folic acid supplement. Recent
evidence suggests that getting too much folic acid may increase the risk of
cancer in predisposed individuals, especially colon cancer.
Folate is needed for the formation and repair of DNA, the genetic material of
cells, and there's some evidence that a deficiency of folate can damage DNA that
may lead to cancer.
Several studies have linked a low folate diet to an increased risk of cancers of
the colon, breast and pancreas.
However, folate's cancer connection is complicated. It may help prevent certain
cancers in some people, but speed them up in others.
What sets people apart is their cancer status at the time they start taking
If they are cancer free, then supplements could help keep some cancers at bay.
But if they already harbour some microscope cancerous or precancerous cells,
then additional folate could make them multiply faster.
For this reason, anyone over 50 and at increased likelihood of having an
undetected cancer, should talk to a doctor before taking folic acid. I advise my
clients to stick with a multivitamin that supplies no more than 0.4 milligrams
of the vitamin, the recommended daily intake.
Not everyone should stop taking folic acid, however. Women of child-bearing age
are urged to take a daily multivitamin providing 0.4 to one milligram of folic
acid. Folic acid is needed for cell division before and during the early weeks
of pregnancy and is vital to preventing neural tube defects (NTDs), serious
birth defects of the brain and spinal cord.
Women at high risk for NTDs – those with epilepsy, Type 1 diabetes, a family
history of NTDs and those who are obese – are advised to take five milligrams a
day of folic acid a few months prior to pregnancy and continue until 12 weeks
While some people may benefit from a B vitamin supplement – be it folic acid,
B12 or B6 – most of us will get what we need to stay healthy from a varied and
Source : CTVglobemedia