Fruit and vegetable juices and Alzheimer's disease: the Kame Project.
BACKGROUND
Growing evidence suggests that oxidative damage caused by the beta-amyloid peptide in the pathogenesis of Alzheimer's disease may be hydrogen peroxide mediated. Many polyphenols, the most abundant dietary antioxidants, possess stronger neuroprotection against hydrogen peroxide than antioxidant vitamins.


METHODS
We tested whether consumption of fruit and vegetable juices, containing a high concentration of polyphenols, decreases the risk of incident probable Alzheimer's disease in the Kame Project cohort, a population-based prospective study of 1836 Japanese Americans in King County, Washington, who were dementia-free at baseline (1992-1994) and were followed through 2001.


RESULTS
After adjustment for potential confounders, the hazard ratio for probable Alzheimer's disease was 0.24 (95% confidence interval [CI], 0.09-0.61) comparing subjects who drank juices at least 3 times per week with those who drank less often than once per week with a hazard ratio of 0.84 (95% CI, 0.31-2.29) for those drinking juices 1 to 2 times per week (P for trend < .01). This inverse association tended to be more pronounced among those with an apolipoprotein Eepsilon-4 allele and those who were not physically active. Conversely, no association was observed for dietary intake of vitamins E, C, or beta-carotene or tea consumption.


CONCLUSIONS
Fruit and vegetable juices may play an important role in delaying the onset of Alzheimer's disease, particularly among those who are at high risk for the disease. These results may lead to a new avenue of inquiry in the prevention of Alzheimer's disease.
Dai
Qi
Q
Department of Medicine, Division of General Internal Medicine and Public Health, Vanderbilt Center for Health Services Research, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, Tenn, USA. qi.dai@vanderbilt.edu
Borenstein
Amy R
AR
Wu
Yougui
Y
Jackson
James C
JC
Larson
Eric B
EB
D000368:Aged; D000544:Alzheimer Disease / Q000453:epidemiology / Q000517:prevention & control*; D044466:Asian People; D001628:Beverages; D015331:Cohort Studies; D003625:Data Collection; D005260:Female; D005419:Flavonoids; D005638:Fruit; D006801:Humans; D015994:Incidence; D007564:Japan / Q000208:ethnology; D008297:Male; D010636:Phenols; D059808:Polyphenols; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014675:Vegetables; D014861:Washington / Q000453:epidemiology
D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols