We are focused on optimizing our food for a specific life stage and what we are putting into each recipe vs. taking away. A growing puppy needs more calories but also has very specific nutrient needs for rapidly growing bones and brains. We use functional ingredients like salmon to provide DHA as well as liver or yeast to help us naturally deliver micronutrients such as copper or zinc. Puppies need upwards of 1.5 times the amount of copper and zinc compared to an adult or senior dog so you may see items fall in a different order on the list of ingredients when comparing adult and puppy recipes due to the nutrients each ingredient is delivering.