STUDY: Dietary intake of folate and risk of stroke in US men and women.

JOURNAL: Stroke 2002;33:1183–9.

AUTHORS: Bazzano LA, He J, Ogden LG, et al

ABSTRACT: The evidence supporting the many health benefits of folic acid has been enhanced with the recent publication of a study in the journal Stroke. The study found that people with a dietary intake of at least 300 mcg per day of folic acid reduced their risk of stroke and heart disease by 20% and 13%, respectively, compared with those who consumed less than 136 mcg of folic acid per day.

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COMMENTARY: After years of research confirming that pregnant women taking folic acid are less likely to have children with neural tube defects, this study is one of the first to demonstrate that dietary intake of folic acid not only reduces heart disease risk, but also prevents stroke. Stroke and heart disease are two of the top three causes of death in the United States.

The new study followed the eating habits of 9,764 men and women between the ages 25 and 74 who showed no signs of heart disease at the beginning of the study. Other trials suggest that 400 mcg per day of folic acid may prevent heart disease by lowering homocysteine levels in the blood. Homocysteine has been shown to be a significant risk factor for heart disease; the risk of having a heart attack goes up as homocysteine levels rise.

The protective effects against heart disease and stroke reinforce the benefits of supplementing with folic acid, which healthcare professionals have long known.

Good sources of folic acid include dark, green leafy vegetables such as kale, Swiss chard and mustard greens, oranges, Brewer’s yeast, soybeans, beets, asparagus, and red meat. Dietary intake can be augmented with folic acid supplements.



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