Via my vet, corn, wheat and soy can be highly allergenic in dogs. Also, sometimes they are added to bump protein levels while using less meat. So, after hearing that, I’ve never fed foods with those ingredients. If my dogs have issues with other ingredients I am feeding, then I will stop feeding the food they’re eating. So far, my dogs have done exceptionally well without eating corn, wheat and soy. This is just the way I want to feed my dogs. I’m not against grains and I do sometimes feed foods with whole grains included in the ingredient panel, like Acana Duck & Pear which contains oats.
