The first diet I would recommend is a gluten free diet. You can look it up on the internet to learn about it (unless of course you've already tried it). You'll need to take gluten free vitamins and check all medications for gluten. Give it a good month and see if it helps. If it helps but doesn't totally eliminate the problem, add milk
diets read up on the supplements that are recommended for each diet - they are there for a reason. A food elimination diary is a good place to start. Everyone is different - so you have to figure out for yourself what foods agree and disagree with you. Hang in there!
Hope this helps.