An analysis by researchers at the UCLA Stroke Center in Los Angeles of 13 clinical trials studying folic acid and stroke found that taking folic acid supplements doesn't appear to prevent strokes. The clinical trials involved more than 39,000 participants with medical histories that included kidney and heart disease as well as stroke. Among the 20,415 study volunteers taking folic acid supplements, 784 suffered strokes, compared to 791 strokes reported among the 18,590 participants who did not take the supplements.

The findings by the research team at the UCLA Stroke Center contradicts earlier studies showing potential benefits in taking folic acid supplements to lower stroke risk. One reason for the difference may be that some of those studies were done in countries in which food supplies are not fortified with folic acid, as they are in the U.S. Fortifying foods with folic acid began in the U.S. in 1998 when the U.S. Food and Drug Administration required that the supplement be added to cereal-grain foods in an effort to reduce the incidence of spina bifida, a serious birth defect in which the backbone and spinal cord fail to close properly.

Folic acid is the synthetic form of folate, a B vitamin naturally found in many foods, including leafy green vegetables such as spinach and asparagus; citrus fruits; and dried beans. Because foods either naturally contain folate or are enriched with folic acid, it may not be necessary to take folic acid supplements, say the UCLA researchers.

Reducing Your Risk for Stroke

Stroke is the third leading cause of death in the U.S. and the leading cause of severe, long-term disability, according to the American Health Association. Managing high blood pressure-140/90 mm Hg or higher-is the single most important thing you can do to lower your chances of a stroke. Making some lifestyle changes can also reduce stroke risk, including:

  • Quitting smoking
  • Eating a healthy diet-Diets high in saturated fat, trans fat and cholesterol can raise blood cholesterol levels and foods high in sodium (salt) can boost blood pressure. Eating a diet high in fruits and vegetables-five or more servings per day-may lower your risk for stroke.
  • Stay active-Leading a sedentary lifestyle or being obese or both can raise your risk for high blood pressure, high blood cholesterol, diabetes, heart disease and stroke. To lower your risk for stroke, aim to get at least 30 minutes of activity most days of the week.

If you're concerned about your risk for stroke, talk to your doctor about the steps you can take to reduce that risk.