Researchers have said that folic acid pills and vitamin B6 and B12 supplements do not reduce cardiovascular risk. The study reported in the Journal of the American Medical Associations, had to be cut short as the pills were not helping the participants and might have caused them harm.

Conducted by physicians at the Haukeland University Hospital in Bergen, Norway, the study found that patients of coronary artery disease taking cardiovascular drugs did not benefit nor reduce their risk of death, nonfatal heart attack or clot-related stroke, despite taking folic acid, vitamin B12, and/or vitamin B6 supplements for about three years.

Alice H. Lichtenstein, Gershoff professor of nutrition at Tufts University, Boston said, "This confirms what a lot of recent studies have found -- no benefit of taking vitamin B supplements to reduce the risk of heart disease, and it raises a few red flags."

The study enrolled almost 3,100 volunteers and three-quarters of them were given doses of vitamin B and folic acid (which is chemically a B vitamin), while the others got a placebo. In Norway unlike the U.S. folic acid is not added to the wheat. Folic acid, a synthetic form of folate, a B vitamin found in many fruits and vegetables, is added to food in the United States routinely because it reduces the incidence of a specific class of birth defects called neural tube defects.

At the start of the study the study patients were on an average in their sixties and more than 75 %of them were taking statins, anti-platelet drugs and beta blockers for their heart problems.

The researchers ended the study early, after a follow up of 38 months.

"We could not detect any preventive effect of intervention with folic acid plus vitamin B12 or with vitamin B6 on mortality or major cardiovascular events," the researchers reported.

A slight reduction of stroke, but also a slight increase of cancer in those taking folic acid, was noted and the study ended early as a different Norwegian study of folic acid and vitamin B supplementation had indicated an increased incidence of cancer among users.

The study was started as observational studies had indicated a link between high blood levels of a protein called homocysteine and an increased cardiovascular risk. The current study did show the homocysteine levels decrease by 30 % over the 3 year period that they took folic acid and vitamin B supplements.

There was however no related effect on cardiovascular risks. Patients taking folic acid and vitamin B12 had a 26 % drop in their homocystein levels, compared to patients who weren't taking folic acid. Despite the drop those patients were just as likely to suffer a nonfatal heart attack or clot-related stroke, be hospitalized due to unstable angina, or need to have a narrowed or blocked coronary artery surgically reopened.

Lichtenstein said, "There is no evidence that individuals should take B vitamins to decrease the risk of heart disease, and there may be some evidence that they shouldn't."

Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in New York City said, "We have been optimistic about the role of antioxidants such as vitamin B in preventing heart disease, yet many of these large trials have shown that there is no benefit. People taking the supplements have good lifestyles in general," Steinbaum said adding that it was difficult to say if the reduction in cardiovascular disease seen in some trials was a result of vitamin supplements.

"But at this point, it is certainly hard to recommend extra supplements when we don't have proof of benefit," Steinbaum said. "What we can recommend is a diet with fruits and vegetables that have antioxidant vitamins in them," she added.

The researchers, who included Marta Ebbing, MD, of Norway's Haukeland University Hospital said, "Our findings do not support the use of B vitamins as secondary prevention in patients with coronary artery disease."