23 Jan 2015 --- The hundred trillion bacteria living in an adult human-mostly in the intestines, making up the gut microbiome-have a significant impact on behavior and brain health. The many ways gut bacteria can impact normal brain activity and development, affect sleep and stress responses, play a role in a variety of diseases, and be modified through diet for therapeutic use are described in a comprehensive Review article in Journal of Medicinal Food, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers.