Results of a large epidemiological study that appears in the September issue of The American Journal of Medicine found that people who drank three or more servings of fruit and vegetable juices per week had a 76 percent lower risk of developing Alzheimer's disease than those who drank juice less than once per week.

The study led by Qi Dai, M.D., Ph.D., assistant professor of Medicine at Vanderbilt University Medical Center followed a subset of subjects from a large cross-cultural study of dementia --the Ni-Hon-Sea Project, which investigated Alzheimer's disease and vascular dementia in older Japanese populations living in Japan, Hawaii and seattle, Wash and in --the Kame Project, where the researchers identified 1,836 dementia-free subjects in the Seattle population and collected information on their dietary consumption of fruit and vegetable juices. Cognitive functions in the subjects were assessed every two years for up to 10 years.

"We thought that the underlying component may not be vitamins, that there was maybe something else," Dai said.

Dai began to suspect that another class of antioxidant chemicals, known as polyphenols, could play a role. Polyphenols are non-vitamin antioxidants common in the diet and particularly abundant in teas, juices and wines.

Most polyphenols exist primarily in the skins and peels of fruits and vegetables. Recent studies have shown that polyphenols (like resveratrol in wine) extend maximum lifespan by 59 percent and delay age-dependent decay of cognitive performance in animal models.

The benefits of drinking more fruit and vegetable juices appeared to be n\more enhanced in subjects who carry the apolipoprotein E ÿ-4 allele, a genetic marker linked to late-onset Alzheimer's disease -- the most common form of the disease, which typically occurs after the age of 65.

More details about the study results can be found at BBC Health News or the Vanderbilt University Medical Center News.