TUESDAY, Dec. 12, 2006 (HealthDay News) -- If you're taking folic acid supplements to try to stave off a second heart attack or stroke, you'd probably get more benefit from making lifestyle changes, such as exercising more and eating right, new research suggests.
In an analysis of a dozen randomized, placebo-controlled clinical trials, researchers found that folic acid supplements do little to reduce cardiovascular disease risk in people who already have a history of heart disease, stroke or serious kidney disease.
"Consuming a supplement of folic acid is probably not going to mitigate your risk of cardiovascular disease," said the study's lead author, Dr. Lydia Bazzano, an assistant professor of epidemiology at Tulane University School of Public Health and Tropical Medicine, in New Orleans.
Results of Bazzano's analysis are published in the Dec. 13 issue of the Journal of the American Medical Association.
According to Dr. Stephen Siegel, a cardiologist at New York University Medical Center in New York City: "The whole concept [of folic acid supplementation] began because we know there's an association between homocysteine levels and atherosclerotic disease, and we know that we can safely lower homocysteine with folic acid. But we don't know if there's a cause-and-effect relationship between homocysteine and cardiovascular disease, or simply an association. Many doctors jumped on the bandwagon, however, because folic acid didn't have the potential to do any harm, but it looked like it might help."
"It was a great thought," Siegel said, but added, "Unfortunately, there's no easy magic bullet. This study cements the evidence presented by other studies that there doesn't seem to be any cardiovascular benefit from folic acid supplements."
For the new study, Bazzano and her colleagues reviewed published literature from 1966 through July 2006 to find studies that had been done comparing folic acid to the use of a placebo in people who had a history of cardiovascular disease.
The researchers found 12 studies that fit their criteria. Together, the studies included data from nearly 17,000 people who took either a placebo or a folic acid supplement for at least six months.
When looking at the studies combined, 18.3 percent of those taking folic acid experienced a cardiovascular event, compared to 19.2 percent of those on a placebo. For heart disease, the rates were 11.4 percent for people taking folic acid supplements, and 10.6 percent for those on a placebo. And 4.7 percent of those on folic acid had a stroke, compared to 5.8 percent of patients on a placebo.
One piece of good news from the study is that taking folic acid appeared to be safe, and it didn't increase the risk for mortality.
"This study provides very important info, and it shows that cardiovascular disease prevention is not as simple as taking a pill," said Dr. Julius Gardin, chief of cardiology at St. John Hospital and Medical Center in Detroit. "I don't know that the final answer on folic acid has been written yet, but this study suggests that folic acid supplementation is not effective for secondary prevention of cardiovascular disease," he added.
Bazzano was quick to point out, however, that this study doesn't mean people shouldn't get folic acid -- which in its natural form is known as folate -- from a healthful diet. Leafy green vegetables and citrus fruits are rich in folate and are important components in a healthy diet. And, eating a healthy diet is a known way to prevent cardiovascular disease.
Other ways of reducing your risk include quitting smoking, lowering your blood pressure and cholesterol, and controlling diabetes, according to Bazzano.
Both Siegel and Gardin said exercise is very important in protecting your cardiovascular health, as well.
"Exercise is probably one of the most critical things that people can do. At a minimum, people should get 30 minutes of activity at least five days a week," said Siegel, who added that most people should also add 40 minutes to an hour of moderately strenuous activity into their routines another two or three times a week.
The U.S. Food and Drug Administration offers advice on keeping your heart healthy.