There is a book in spanish titled "drogas inteligentes" (smart drugs) it goes on the topic of vitamins or substances that help the brain, then goes on food that that is rich on this vitamins.
The target public for this book, is chess players.
I personaly question a lot of the info on this book, still I think the concept is interesting and would like to see a better research on the topic.
here watch this. they have the recipe for a good chess meal. eat this and you are ready for chess :-)
http://www.youtube.com/watch?v=7Xc5wIpUenQ