[Ellie May]

As Maximo said, it's a great debate.

I think pretty much everybody agrees (vets and vet nutritionists, etc.) that high protein doesn't cause kidney or liver problems (although I'm sure more studies are being or will be done on this). However, high protein is not necessarily good for most liver and kidney issues (high protein usually comes with high phosphorus which already failing kidneys don't like, etc.). So these problems really should be ruled out first before choosing a high protein food. But the problem is liver and kidney issues don't always show up on blood work or urine testing until the disease process is advanced (many middle aged dogs have the beginnings of kidney failure and nobody would know it because routine testing doesn't catch it this early - the kidney hasn't been damaged enough yet). And so to give a dog high protein/high phosphorus food just because their lab work looks good may not be such a good idea.

The BUN tends to climb in dogs fed high protein diets too. It's very much a matter of to each their own (and I hope people are talking to their vets before deciding to feed a food like this). For my dogs, I don't feel that high protein is appropriate unless a veterinary nutritionist recommended it for them. I will not watch the BUN in my dogs climb in the name of feeding a species appropriate diet, nor am I comfortable using it based on good lab results. Good labs don't always equal healthy dog. JMO