I researched a lot on diets for kidney issues when my last dog started having problems. I had to do in depth research, because she also had diabetes and couldn't have the carbohydrates. More recent studies done and a lot of homeopathics and holistic vets/scientists believe the low protein diet is not more beneficial, as long as the protein is a high quality. Haley's BUN level was near the high end of the normal range even the first time I had her blood work done (a couple weeks after I adopted her). From my reading, it doesn't necessarily mean kidney problems when only the BUN levels are high, but I'm just really paranoid after dealing with kidney failure on top of the other health issues in my other dog. I did read about a couple of supplements that are manufactured for veterinary uses (therefore, expensive) that are being used for kidney problems. You're not going to believe what they are --- one was just probiotics and the other was chitosan and something else. Basically, they are charging a lot for simple supplements that can be purchased. I already give Haley probiotics every day, but I haven't tried the chitosan.