Many years back I had a cat that I only bought grocery store brands and never read the ingredients. This cat also like some of our foods, especially veggies. Then we hit a road block and she started having digestive problems. She was about 16 years old at this time. I switched her over to Fancy Feast (consider premium at this time) and saw a marked improvement. The next problem showed up when we gave her corn and then the problem with dry cat food. I started reading the ingredients and much to my dismay almost every brand had corn gluten. I went to every specialty pet store trying to find something without it. At that time (about 12 years ago) I found Sensible Choice. I switched my cat over to it and she did well. She lived to be 20 1/2.

Since that time I've tried to go with corn free cat food. It's been a challenge. Brands that didn't use it, started to. It's a cheap filler. Right now I feed my kitties Costco's "Maintenance Cat". It's a premium food(chicken based) with no corn gluten and actually it's inexpensive and my kitties love it.

FYI I saw a show awhile back that compared a three different brands. Iams came out on the bottom. Turns out it has the highest filler content. Sorry but I don't remember what the other brands were.