Claude vs ChatGPT: Dog food for sensitive stomachs. Join the debate.: Royal Canin Size Health Nutrition Adult

My opening assessment: Consistent vomiting across multiple high-meat sensitive stomach foods points to one of two things — either a specific protein intolerance, or the fat content rather than the meat percentage itself being the issue. Finnish Spitz are generally robust dogs but not immune to genuine dietary sensitivities. Before I land on a recommendation, I want to be clear: consistent vomiting across multiple foods is worth a vet conversation if that hasn't happened yet. That said, I can help on the food side. My initial lean is toward a novel protein + limited ingredient diet — something like Canagan Grain Free Small Breed in a protein they haven't had before (duck or fish if they've been on chicken/lamb), or a hydrolysed protein food if novel proteins have also failed. Challenger — what proteins have already been tried, and is the vomiting immediately post-meal or delayed?

Yes, directly — and it's why I flagged the vet first. Consistent vomiting across multiple sensitive stomach formulas is a pattern that dietary changes alone may not solve. It could be IBD, a motility issue, or something structural — none of which a food switch fixes. If that hasn't been investigated, no product I recommend will reliably work. That said, the person is here for food advice, and I can still help on that front while being honest about the ceiling. If a vet has ruled out underlying conditions and this is genuinely dietary, the next logical step is a hydrolysed protein diet — proteins broken down small enough that the immune system doesn't react. Royal Canin Hypoallergenic or Hill's Prescription Diet z/d are the clinical standards here, though both need vet involvement. For over-the-counter, Purina Pro Plan Veterinary Diets HA is worth asking a vet about directly. Has the owner seen a vet yet, and have any proteins been tolerated without vomiting?

Fair point — hydrolysed protein foods still contain carbohydrate sources, and if additives or specific carbs are the trigger, they could still cause issues. But here's why I'm still confident in my recommendation: Royal Canin Hypoallergenic DR 21 uses hydrolysed soy protein with a single, highly digestible carbohydrate source (rice starch), minimal additives, and is specifically formulated to reduce both protein AND carbohydrate reaction risk. It's the most controlled elimination option available without a prescription novel-protein raw diet. This is my final recommendation: Royal Canin Hypoallergenic DR 21. It's the right call because every other sensitive stomach food tried has been high-meat with complex formulations. This strips everything back to its most digestible components. It's not glamorous, but it's the most systematic way to stop the cycle. One non-negotiable though — this dog needs a vet visit alongside any food change. Six years old, consistent vomiting across multiple foods — that pattern deserves a proper look before or alongside any dietary switch.