by Shana Potash
Two decades ago, research in China demonstrated that folate supplementation in pregnant women could reduce incidence of birth defects. Research conducted in China recently found that it can also reduce the risk of stroke in people with high blood pressure. Hypertension is a major risk factor for stroke, which is the leading cause of death in China and the second leading cause of death worldwide.
Scientists studied more than 20,000 men and women with high blood pressure who had never had a stroke or heart attack. Participants who took folic acid along with a blood pressure drug were less likely to have a stroke than people who took the drug alone. The combination reduced the risk of having a first stroke by 21 percent. The folic acid therapy provided the most benefit for people who had the lowest levels of folate in their blood at the start of the trial.
Folic acid is the synthetic form of the B vitamin folate, which is found in green leafy vegetables and in many fruits, beans and nuts. Some countries, including the U.S., require that grains be fortified with folic acid. Past studies have found folic acid supplements had little effect on cardiovascular disease but the China trial was conducted in a part of the world where folate levels are low.
The findings were published recently in the Journal of the American Medical Association (JAMA) and could have "important implications for stroke prevention worldwide," according to Drs. Meir Stampfer and Walter Willett of Harvard University, in an accompanying editorial. They noted large segments of the world's population, including people in northern China, Bangladesh and Scandinavia, have low levels of folate. Some U.S. residents also fall into that category.
Previously, Chinese scientists collaborated with the U.S. CDC to examine the benefits of folic acid consumption before and during pregnancy, concluding that the supplement significantly reduced the risk for neural tube defects in infants.