OMG, I have been reading ingredients and comparing brands, and there is alot to take in. I have a fat cat and a skinny cat. I bought Royal Canin Slim 38 for the tubby one and it looks like good ingredients with no by products. And I bought the skinny one some Science Diet Natures Best, but am not decided on it being one of the best. Anyone done the homework? Next I am going to check out Flint River something...anyway I know where to find it on the net. Linda