I don’t know if it gives cats smelly poop and gas, Ashley, but I saw a flyer about grain-free food on my vet’s bulletin board when I took Penny in to have her teeth cleaned. It said that the idea that dogs and cats need grain-free food is a myth and listed the nutrients that animals need that grain provides. I didn’t get to finish reading it before they took Penny back, but I don’t recall seeing any food manufacturer’s logo on it.
Several months ago, my vet also sent out an e-newsletter in response to the commercials for the Blue food line that complain about foods that don’t have “real meat” as the first ingredient. The vet said that pets need nutrients, not particular ingredients, and that a variety of ingredients can give them the nutrients they need.
Another thing to remember is that, in the wild, felines and canines do not have grain-free diets. This will sound gross, but wild animals consume the entire prey. In so doing, they consume what the prey consumed; if the prey ate grain, the wild animal gets the grain.