What's actually in Instinct?
We analyzed Instinct Original Grain-Free Real Chicken Recipe. The first two ingredients are chicken and chicken meal — whole protein followed by concentrated protein, a quality opening. Peas follow at position three, then chicken fat at four and tapioca at five. Herring meal and menhaden fish meal at positions six and seven add additional animal protein diversity, followed by natural flavor, dried tomato pomace, and salt rounding out the top ten.
The formula is straightforwardly grain-free, with peas and tapioca doing the carbohydrate work that grains would otherwise do. Peas at the third position is still notable in the context of the FDA's DCM investigation into legume-heavy grain-free diets, though the formula is not as legume-concentrated as some competitors — chicken fat and tapioca fill the fourth and fifth spots rather than additional pea derivatives. Shop on Amazon →
The good stuff
Chicken and chicken meal in positions one and two deliver solid animal protein density before the first carbohydrate. Herring meal and menhaden fish meal at positions six and seven provide additional animal protein from marine sources — a meaningful plus that also delivers EPA/DHA omega-3 fatty acids. No corn, wheat, or soy. Chicory root extract provides prebiotic fiber — a positive for gut health that many grain-free brands omit. Blueberries and raspberries add antioxidants. Flaxseed provides plant-based omega-3s (ALA) for skin and coat support.
Instinct is a clean brand in the sense that the problematic fillers and artificial additives common to mainstream kibble are absent. The formula's problems are structural, not cosmetic.
The not-so-good stuff
Peas at position three is the primary concern. The FDA's investigation into dilated cardiomyopathy (DCM) in dogs eating grain-free, legume-heavy diets remains directly relevant to any grain-free formula with legumes this high on the list. No causal link has been established, but grain-free formulas with prominent legume placement are among the most studied. For dogs predisposed to cardiac conditions (Dobermans, Boxers, Golden Retrievers, Great Danes), discuss this with a vet before feeding long-term.
The formula is entirely grain-free, which means peas and tapioca carry the full carbohydrate load — there are no grains to balance the legume content. No probiotics either.
How it compares
At C/70, Instinct sits near the top of the C tier — just below the B threshold. It scores higher than the mainstream vet-recommended brands (Purina Pro Plan C/62, Hill's Science Diet C/61, Royal Canin C/58) but not because of superior ingredient quality — the DCM concern is the primary reason it sits below B territory.
Compared to other grain-free options: Blue Buffalo Wilderness (B/75) scores higher, managing a slightly better legume-to-protein balance. Taste of the Wild (B/78) also handles the legume balance better at a lower price than either. For dogs that need grain-free, those options are more defensible.
Read the full breakdown in our Instinct vs Purina Beyond head-to-head comparison.
Cross-format sibling: for Instinct's freeze-dried raw cat topper (NOT a complete diet), see our Instinct Raw Boost Mixers Cage-Free Chicken Cat Topper (B/79) review scored under the Fresh Food Rubric v1.0 §16 mixer rules.
The bottom line
Instinct Grain-Free earns a C grade (70/100) from KibbleIQ. Quality chicken protein sourcing, marine protein from herring and menhaden fish meal, and a clean label are strong positives — but peas at position three in a fully grain-free formula keep it at the center of the DCM discussion. If your dog has a grain intolerance and you need grain-free, Taste of the Wild handles the legume balance better at a lower price point. If grain-free isn't a requirement, Wellness Complete Health or Merrick Classic offer a meaningfully better ingredient profile. Shop on Amazon →