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. How it works: *Controlled phosphorus & low sodium *High level of essential amino acids - the building blocks of muscle protein *Therapeutic levels of L-Carnitine and Omega-3 fatty acids How it helps: *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 Additional info: Hill's® Prescription Diet® k/d® Feline is a complete and balanced food that provides all the nutrition your cat needs. Please consult your veterinarian for further information on how our Prescription Diet foods can help your cat to continue to enjoy a happy and active life. Ingredients: INGREDIENTS: Water, Pork Liver, Carrots, Tuna, Chicken, Rice, Rice Starch, Chicken Fat, Spinach, Pea Protein, Hydrolyzed Chicken Flavor, Sunflower Oil, Powdered Cellulose, Fish Oil, Potassium Alginate, Coconut Oil, L-Threonine, Egg Whites, Calcium Lactate, Calcium Gluconate, Potassium Citrate, Natural Flavor, Guar Gum, vitamins (Vitamin E Supplement, Thiamine Mononitrate, Ascorbic Acid (source of Vitamin C), Niacin Supplement, Menadione Sodium Bisulfite Complex (source of Vitamin K), Pyridoxine Hydrochloride, CalciumPantothenate, Vitamin A Supplement, Vitamin B12 Supplement, Riboflavin Supplement, Folic Acid, Biotin, Vitamin D3 Supplement), Choline Chloride, Taurine, L-Arginine, Calcium Chloride, Dicalcium Phosphate, L-Carnitine, minerals (Zinc Oxide, Ferrous Sulfate, Copper Sulfate, Manganous Oxide, Calcium Iodate), Sodium Tripolyphosphate, Beta-Carotene, Calcium Carbonate. Nutrient Dry Matter Protein 30 % Fat 25.7 % Carbohydrate / NFE 36.4 % Crude Fiber 2.8 % Calcium 0.85 % Phosphorus 0.5 % Potassium 1.2 % Sodium 0.24 % Magnesium 0.06 % Taurine 0.49 % Vitamin C 137 ppm Vitamin E 936 IU/kg Total Omega-3 FA 1.21 % Total Omega-6 FA 4.57 %