Large Medical Study Concludes
Folate Decreases Risk for High Blood Pressure
Publisher's abstract: Journal
of the American Medical Association. 2005;293:320-329
Women who get large amounts of the vitamin folate from food and
supplements have a sharply lower risk of developing high blood
pressure, according to researchers from Brigham & Women's
Hospital and Harvard Medical School in a study of 150,000 women.
In the first large study to explore the link between folate and
hypertension, women ages 27 to 44 and ages 43 to 70 recorded their
folate intake over an eight-year period. Younger women who consumed
at least 1,000 micrograms of folate per day — or 2 1/2 times
the recommended daily allowance — were 46% less likely to
develop hypertension than women who consumed less than 200 micrograms.
Older women saw a less pronounced yet significant 18% reduced
risk of high blood pressure after consuming 1,000 micrograms of
folate each day.
The study, published in the Journal of the American Medical
Association, concluded that women who got only got folate
from food, instead of from supplements, had difficulty attaining
high enough levels to lower blood pressure.
"We found that a higher folate intake was associated with
a lower risk of developing high blood pressure." said Dr. John Forman of Brigham and Women's Hospital in Boston
affects an estimated 65 million individuals in the U.S. and many
more worldwide. The purpose of this study was to determine whether
higher folate intake is associated with a lower risk of hypertension.
"The theory," says CBS News medical correspondent Dr.
Emily Senay, "is that folic acid somehow keeps blood vessels
supple, or less stiff, and so helps keep blood pressure down."
Other research has shown that up to 70 percent of birth defects
of the brain and spine, and many cases of Down Syndrome can be
prevented by maintaining adequate folate levels before and during
pregnancy. Studies have also shown folate to be important in preventing
Foods as oranges, dark green leafy vegetables, beans, legumes,
liver and eggs are highest in dietary folate. In the United States,
folic acid is added to cereal and flour products to help prevent
Sources: Media Reports and publisher's abstract
- Additional studies are needed to determine
whether folate intake has a direct, causal role in risk
reduction for hypertension.
- Because this was an observational study, it
is possible that other factors may be responsible for the
reduction in risk. People with a high intake of one nutrient
are likely to have a high intake of several nutrients, and
may generally have a healthy lifestyle.
- Intake of more than 1000 mcg/day of folate
can hide symptoms of B12 deficiency. A blood test can measure
serum B12, or see if methylmalonic acid is elevated as a
proxy for functional B12 shortage. Oral supplementation
with 1000 mcg/day of B12 corrects or protects against most
cases of deficiency (except those due to metabolic or serious
malabsorption issues). If untreated, B12 deficiency can
result in nerve damage.
- This article is not intended to replace the
advice or attention of your doctor or other health care
professional. Do not stop taking medications or start taking
a nutrition supplement without first speaking to a qualified
health care professional.