We use ‘Medium’ to refer to dogs whose adult weight is between 11kg and 25kg. Medium-sized dogs are famous for their energy, and were historically working dogs. The Royal Canin Medium Size Health Nutrition diets are formulated for specific life stages and also in diets to help strengthen the immune system and promote optimum weight and a healthy skin and coat. Also available in diets formulated to specifically help address sensitive digestion, sensitive skin and weight gain.