My own experience: I found the most helpful was using a good probiotic such as Primal Defence and EXERCISE! If you're the kind of person that's sitting down more than not, then your body is likely not getting proper movement to keep your body working as well as it could plus your spine could likely be out of shape (nerves get pinched/attenuated) .
After several worrying symptoms I got a chiropractor to diagnose my spine (I had several distortions which needed to be fixed up). Along with this I discovered that a daily regiment of streches are what really did the trick. This got the blood flow where it was needed (abdominal/digestion)and kept everything properly moving. Consult a good yoga instructor for specific exercises for digestions etc.
Several foods are detrimental; coffee (my gums shrink), sugar, frozen treats. Things that help the most are lots of green Romain lettus, carrots, cucumber etc. Check into food combining rules.
Hope this helps some, I still have more work to do but this helped me so far..