An ingredient inside grapes, green tea & chocolate blocks the toxic amyloid beta that can build up in the brain causing Alzheimer's. This study was done on mice but the mice took the same amount of polyphenolic compounds inside grapes that an average person can take per day.

An analysis of the grape seeds used showed the major active ingredients are catechin and epicatechin, which are also abundant in tea and cocoa.

Another antioxidant from grapes that has been in the news lately is resveratrol. Resveratrol seems to only be effective at protecting against Alzheimer's at extremely high doses. Catechins in the extract product studied appear to be effective at practical doses.

The Journal of Neuroscience
June 18, 2008 • Volume 28 Number 25
6388 Grape-Derived Polyphenolics Prevent A Oligomerization and Attenuate Cognitive
Deterioration in a Mouse Model of Alzheimer’s Disease
Jun Wang, Lap Ho, Wei Zhao, Kenjiro Ono, Clark Rosensweig, Linghong Chen,
Nelson Humala, David B. Teplow, and Giulio M. Pasinetti

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