Iams is in there with the crappy stuff. As a rule if you can find it in the grocery store it is not a good dog food. In order to produce the quantities needed to fulfill the grocery stores needs they need to use a lot of fillers. Try going to a specialty store where they have high end kibble like Innova and Origen. Try giving her a piece of raw steak and see what she does. What are her stools like. She may not want to eat it if is does not agree with her. An awful lot of dogs do not do well with grains and frankly they just do not need them. Are you just leaving the food out for her to eat or feeding her at specific times?