Consider looking into FODMAP diet and elimination technique. FODMAPS are fermentable
1. oligosaccharides: fructans and galactans
2. disaccharides: lactose
3. monosaccharides: fructose
4. polyols (sugar alcohols): sorbitol, mannitol, malitol, xylitol
The research is out of Australia and is looking very promising! This may be your answer to end the constant bloating, constipation or diarrhea.