The kidneys filter waste and toxins from the blood and maintain the normal balance of fluid and minerals within the body. As pets age, damage to kidney tissues may occur. This process is irreversible and leads to loss of kidney function. Cats with decreased kidney function may experience loss of appetite and their food intake might decline, which may lead to loss of muscle mass. Hill's nutritionists and veterinarians developed Prescription Diet® k/d® clinical nutrition to support your cat's kidney function and help sustain muscle mass. In fact, the nutrition of k/d is clinically tested nutrition to improve & lengthen quality of life. -Protects vital kidney & heart function -Supports your cat's natural ability to build lean muscle daily -S+OXSHIELDTM: Formulated to promote a urinary environment that reduces the risk of developing struvite & calcium oxalate crystals INGREDIENTS: Water, Chicken, Pork Liver, Brewers Rice, Tuna, Modified Rice Starch, Dried Whey, Chicken Fat, Hydrolyzed Chicken Flavor, Fish Oil, Egg Product, Powdered Cellulose, Guar Gum, Calcium Carbonate, Potassium Citrate, Natural Flavor, L-Arginine, vitamins (Vitamin E Supplement, Thiamine Mononitrate, L-Ascorbyl-2-Polyphosphate (source of Vitamin C), Niacin Supplement, Menadione Sodium Bisulfite Complex (source of Vitamin K), Pyridoxine Hydrochloride, Calcium Pantothenate, Vitamin B12 Supplement, Riboflavin Supplement, Folic Acid, Biotin), Betaine, Whole Grain Oats, L-Threonine, Taurine, Fructooligosaccharides (FOS), Choline Chloride, L-Carnitine, minerals (Zinc Oxide, Ferrous Sulfate, Manganese Sulfate, Copper Sulfate, Calcium Iodate), Beta-Carotene. 174 kcal / 5.5 oz (156 g) can Nutrient Dry Matter% Protein 29 % Fat 22.2 % Carbohydrate / NFE 42.1 % Crude Fiber 1.4 % Calcium 0.91 % Phosphorus 0.52 % Potassium 0.93 % Sodium 0.26 % Magnesium 0.061 % Taurine 0.42 % Vitamin C 116 ppm Vitamin E 998 IU/kg Total Omega-3 FA 1.08 % Carnitine 550 ppm *The nutrient in the product after moisture is removed. It is used to make direct comparisons of nutrient profiles with differing moisture contents.