The main issue with grain is the protein gluten.If you had the anti-gliadin antibody test and it came back positive then avoiding gluten is a wise thing to do.Wheat grass does not contain gluten so there will be no problem with grass juice.Sprouted grain does digest easier than non sprouted grains.You can use buckwheat which has no gluten and there are other alternatives as well.It is not natural to be allergic so clean up your diet and your body will reset itself to balance things out.Be well and at peace with all things.