I've went gluten free and various other elimination diets. I find that sugars are very bad for me and I'm cutting them out slowly, then soon completely. I was doing this for stomach ibs issues but, I wonder about the food/mood thing. I always get discouraged because I don't think I'm getting enough relief. Then I go back to old ways of eating and realize it helped more than I realized. I saw a lady on YouTube who ate clean and it took 3 years to heal herself, but she said she felt 100% better. This was physical, not mental health. I would be thrilled if food turns out to cure both physical and mental illness. I'm skeptical, but hopeful.