I love it when I find a study that helps validate the intake of my favorite foods (in moderation, of course).
In this case, according to Oxford researchers working with colleagues in Norway, chocolate, wine, coffee, and tea enhance cognitive performance.
The researchers believe it has something to do with the high amounts of polyphenols in these foods. The largest subclass of dietary polyphenols is flavonoids, which seem to result in a lower incidence of dementia.
Researchers do, of course, recommend moderation. 
Happy Holidays!
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