There is no scientific reason to feed a low protein diet to pets with chronic kidney failure. Nutritionists say that restricted protein has minimal if any effect on kidney failure. Uraemia is managed by maintaining nitrogen balance and this is done by reducing dietary phosphorus. Because protein is a major source of phosphorus feeding a medium protein, low phosphorus diet is now recommended.
Supplementing the diet with Omega 6 polyunsaturated fatty acids (Omega-6 PUFA) appears to damage kidneys while Omega-3 PUFA supplementation appears to protect the kidneys (and lower blood pressure in people). Omega-3 PUFA supplements or diets already containing these fatty acids may be an effective therapy for pets with kidney failure. There is no known benefit in adding saturated fatty acid supplements. Free radicals damage kidney cell membranes. Antioxidant dietary supplements scavenge free radicals reducing kidney damage. Most pet food manufacturers, including Hills, Royal Canin Waltham and Purina add antioxidants to their specialty diets.