I created an account just to respond to this, because it took me a long time to learn about this same issue.
My dog has a bunch of allergies — still sorting through them — and she started having problems with supplements that had digestive enzymes in them. Long story short, a lot of what’s used in kibble and supplements comes from aspergillus, which is a mold species. If your dog has yeast or mold sensitivities, those enzymes can cause problems. I abandoned them, closest thing she gets now is goat’s milk with probiotics in it, which really seems to help with keeping her system settled.
I hope this is helpful, and please keep in mind I’m not an expert or vet so some of what I say may be wrong.
