My dogs were doing fine on beneful..and I switched to a better food, Kirkland Signature (not the best, but much better than Purine beneful) and they are EVEN better! So I bet if you switched to a better food, you would notice an even great improvement!! My mom used to feed them Science diet, and again..they were fine on that food as well, but EVEN better on their current food. The only thing I did notice, when Peanut was eating Beneful he didn't have bad tear stains..and now he has bad tear stains on the Kirkland...I am working on switching his food to a higher quality food. Hes very picky though. (And not for the sake of argument!! Just saying, how do you know your cat will only eat purina if you said that's all hes ever eaten?). My cats ate Meow mix for many years, and they easily transitioned to Kirkland Signature.) Edit to add: My dog Brad was on Science diet and then Beneful and had REALLY terrible skin allergies. My mom denied that it was the food, and even the vet didn't think it was the food (Which is why I would never listen to a vet when it comes to dog nutrition). He lived most of his life with balding skin, scratching and biting himself all over...being red and inflamed. And then a couple weeks after we switched to Kirkland, his fur grew back in, he didn't scratch at all. And his fur was beautiful and soft and shiny and silky!