MINNEAPOLIS (CNN) -- There is more evidence that vitamin B-6 may help prevent heart disease. Researchers found those who had high levels of the antioxidant had a one-third lower risk of heart disease compared with others in the study who had low levels.

The study, published in this week's American Heart Association journal, Circulation, was originally meant to study whether the substance homocysteine affected the risk of heart disease.

University of Minnesota researchers looked at 759 healthy people over three years and did not find a significant correlation between homocysteine, which is a by-product of the body's metabolism of certain foods, and an elevated risk of heart disease in healthy adults.

What they did see is that those with the lowest risk of heart disease had the highest levels of vitamin B-6 in their systems, suggesting that vitamin B-6 might help prevent the onset of atherosclerosis, or clogging of the arteries.

Previous studies have shown a correlation between heart disease and the antioxidant vitamin B-6. Researchers writing in the Journal of the American Medical Association found women with high intakes of vitamin B-6 and folic acid had a 45 percent lower risk of developing heart disease.

Researchers are now conducting clinical trials before they suggest any possible increase in the daily recommended allowances for vitamin B-6 for heart disease prevention.

CNN Food & Health Correspondent Holly Firfer and Reuters contributed to this report.