B Vitamins Reduce Stroke, Heart Disease Deaths
Benefits of Folate and B6 Apply to Men and Women, Researchers Say
April 15, 2010 -- Foods rich in B vitamins such as folate and B-6 may reduce
the risk of death from stroke and heart problems, Japanese researchers say.
Their study looked at the effects of B vitamins on men and women separately,
but findings suggest that foods containing the B vitamins might benefit people
of both sexes.
Their primary findings:
- Folate and B-6 may reduce the risk of heart failure in men.
- The same vitamins seem to reduce the risk of death from stroke and heart
disease in women.
Sources of folate include vegetables, fruits, whole or enriched grains,
fortified cereals, beans, and legumes. B-6 sources include fish, vegetables,
liver, meats, whole grains, and fortified cereals.
Vitamin B6, Folate Fight Heart Disease
The researchers examined data from 23,119 men and 35,611 women between ages
40 and 79 who completed questionnaires about dietary habits as part of the
Japan Collaborative Cohort Study.
They found that at a median of 14 years follow-up, 986 people had died from
stroke, 424 from heart disease, and 2,087 from all diseases related to the
Patients were divided into five groups based on their intake of folate,
vitamin B6, and vitamin B12. Researchers compared people with the diets lowest
and highest for each nutrient and found that higher consumption of folate and
B6 was associated with significantly fewer deaths from heart failure in men. In
women, they detected significantly fewer deaths from stroke, heart disease, and
total cardiovascular deaths.
Vitamin B12 was not found to be associated with a reduced risk of
The protective effects of folate and vitamin B6 did not change even when
researchers made adjustments for the presence of cardiovascular factors or when
people taking supplements were eliminated from the analysis.
The researchers say B6 and folate may fight cardiovascular disease by
lowering levels of homocysteine, an amino acid in the blood that is affected by
diet, but also heredity.
The researchers say the findings on the value of B vitamins were consistent
with studies in North America and Europe. Homocysteine is believed to cause
damage to the inner linings of arteries, promoting blood clots.
B Vitamins: More Research Needed
Hiroyasu Iso, MD, professor of public health at Osaka University and one of
the study authors, says in a news release that people in Japan need to increase
consumption of foods containing folate and vitamin B6.
The researchers say the correlation between intake of folate and B vitamins
with cardiovascular disease is controversial and that evidence of benefits has
been limited to Asian populations. Given their findings, the researchers say
there is an urgent need for more research aimed at replicating the results of
their study in different populations.
The study is published in the April issue of Stroke: Journal of the
American Heart Association.
The Institute of Medicine (IOM), the health arm in the U.S. of the National
Academy of Sciences, recommends 1.3 to 1.7 milligrams of vitamin B6 per day,
depending on age and sex. The IOM says extremely high-dose folate supplements
should be avoided and recommends adult intake of 400 micrograms daily.