The #1 ingredient of this formula is lamb meat, which is hypoallergenic protein. It provides high protein and promotes muscles growth. In addition, joints are strengthened, protected and rebuilt by natural Glucosamine and Chondroitin from lamb. Since brown rice is the source of carbohydrate, it is easily rehydrated and digestible. Moreover, this formula also includes natural antioxidant from Rosemary and Vitamin E. You can be confident that your beloved cats will be specially taken care of by SmartHeart® Gold.