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Heart beat: Blood pressure and a B vitamin

Heart beat

Blood pressure and a B vitamin

Folic acid, one of the eight B vitamins, plays a key role in preventing spina bifida and anencephaly in newborns. These two birth defects occur when the tube that ultimately becomes the spinal cord, brain, and surrounding bone doesn’t close as it should. In adults, folic acid also helps reduce levels of homocysteine, and so may play a role in preventing heart disease. Now a new report suggests that getting plenty of this vitamin could help keep blood pressure in check.

In a study of more than 150,000 female nurses, 20,000 developed high blood pressure over an eight-year period. Compared with women who got less than 200 micrograms (mcg) of folic acid a day — well below the daily recommended intake of 400 mcg — those who took in 1,000 mcg a day were half as likely to have developed high blood pressure.

This link between folic acid and high blood pressure doesn’t come out of the blue. Supplements of folic acid have been shown to improve the flexibility of arteries, an important factor in blood pressure control. Diets such as the DASH diet that are rich in fruits and vegetables, and so teeming with folic acid, also improve blood pressure.

This new study bolsters the latest dietary guidelines, which call for getting nine servings of fruits and vegetables a day, up from the five a day we’ve gotten used to striving for. It also supports using a daily multi-vitamin; most types deliver 400 mcg of folic acid.

Last updated:	August 21, 2006