The basics:

The mind and body are greatly effected by the trillions of microbes which dwell within your gut.

Eat well, use probiotics and prebiotics, and thus foster the growth of beneficial organisms in your intestines.

Keep a healthy intestinal lining (with a healthy, high fiber diet): This will keep the toxic products of pathogenic organisms within the gut and not in the bloodstream.

The specifics and diet can be find in the internet, and this attached article is open source and a good review of the material.

http://pdfs.journals.lww.com/co-psychiatry/2015/01000/The_gut_microbiome_and_diet_in_psychiatry___focus.2.pdf?token=method%7CExpireAbsolute;source%7CJournals;ttl%7C1428895617651;payload%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;hash%7COGo/sbY1lPUwzUPWfoFfIA==&UserName=joriswiggers
The_gut_microbiome_and_diet_in_psychiatry___focus.2.pdf