According to the researchers at the University of Otago in New Zealand who conducted a two-year study on the effects of the vitamins on 276 people 65 and older, folate and B vitamins decrease homoscysteine, a blood substance that can make arteries stiffen and clog.
Studies in the past have shown that people with higher levels of homosysteine also have an increased risk of heart disease, Alzheimer's and other types of dementia, but it is not known whether lowering homocysteine can prevent these diseases.
In the New Zealand study, the homosysteine levels of those taking the supplements - which contained 1,000 micrograms of folate, 500 micrograms of B-12 and 10 milligrams of B6 - did fall. However, both the placebo group and the vitamin group performed the same on several tests used to measure cognitive function.
The findings of the study were published in Thursday's New England Journal of Medicine.
Other studies are underway to see whether taking the pills for a longer time or starting to take them at an earlier age will have any benefit.
