Creatine
This is a compound found in meat, used by athletes to help build muscle. Now the evidence is here to show that it helps your brain as well. Proceedings B , a journal published by the Royal Society reports that the research showed improvement in working memory and general intelligence resulting from creatine supplementation. The dose used in the study was 5 grams per day. This is about the level used to boost sports performance, and is as much as you'd normally get in four pounds of meat, according to lead researcher Dr. Caroline Rae.