When you say "pushing the salt and protein" do you mean he wants you to limit them? You make it sound like he wants you to eat them. I can see that if you were on some kind of very limiting diet and you weren't getting enough sodium which can cause hyponatremia and protein is an essential nutrient for the body to function properly. If prior to your diagnosis you were on the Standard American Diet (SAD) I would assure you you were getting excess sodium and protein and with CKD these should be restricted. I would clarify with your nephrologist and ask for an explanation or seek a second opinion.