Your skepticism is understandable and shared by many pet owners who look closely at ingredient lists. While Hill’s Science Plan is extensively tested for nutritional adequacy and is trusted by many vets, the presence of ingredients like corn and by-products does raise valid questions about quality versus necessity. Some dogs thrive on it, but others show improvements in coat, digestion, or energy after switching to diets with more novel proteins or fewer fillers, whether these are premium commercial options or carefully balanced home-cooked meals. If you’re seeing better outcomes after switching, that’s meaningful—each dog is unique, and what’s “best” often comes down to individual response rather than brand reputation alone.