I guess what I should do first is hit up a library database and find out if anyone has already researched this.
Don't think it'll help you much -- you need to find out how you work, not what happens to some sample of some population of people none of whom are you.
In your place I'd start keeping a detailed mood/mental state diary AND a detailed food diary. After a few months you should be able to get a decent idea of what kinds of food do what to you.
You might also want to talk to gwern -- he does "how X affects me" mini-studies and has good methodology.
Sorry, I didn't make the intent clear. I do want to do more experiments on myself, and I need to work on figuring out a non-annoying way to collect data so I can do that. But I'm also really curious how common this sort of thing is in other people. So the library research is for testing your alternate hypothesis, and my hypothesis that some people are strongly influenced by food but mistake it for a chronic problem.
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