The scores
Royal Canin Maine Coon: C (58/100)
Blue Buffalo Cat: B (76/100)
An 18-point gap is substantial. It's the difference between a food built around by-product meal and corn and one built around deboned chicken and whole grains. Royal Canin's breed-specific marketing is compelling, but the ingredient list tells a different story than the packaging.
How the ingredients compare
Here are the first five ingredients side by side:
Royal Canin Maine Coon: Chicken By-Product Meal, Brewers Rice, Chicken Fat, Corn, Corn Gluten Meal
Blue Buffalo: Deboned Chicken, Chicken Meal, Brown Rice, Barley, Oatmeal
Blue Buffalo has two quality protein sources up front — deboned chicken (whole meat) and chicken meal (concentrated animal protein). Royal Canin starts with chicken by-product meal, a lower-quality protein source made from necks, feet, intestines, and undeveloped eggs. After that, RC leans on brewers rice (a milling by-product), corn, and corn gluten meal — three filler-grade carbohydrates. Blue Buffalo counters with brown rice, barley, and oatmeal — three quality whole grains that provide fiber and slow-release energy.
Where Blue Buffalo pulls ahead
Deboned chicken first. Whole meat as the first ingredient means real animal protein is the foundation of the formula, not a by-product derivative. This is the single biggest quality indicator in any pet food.
Quality grains throughout. Brown rice, barley, and oatmeal are whole grains that provide genuine nutritional value — fiber, B vitamins, and sustained energy. Compare that to RC's corn and corn gluten meal, which are cheap fillers that inflate protein numbers without delivering the amino acid profile cats actually need.
No corn, wheat, or soy. Blue Buffalo avoids the three most common filler ingredients in budget pet food. These are the same ingredients that show up in the lowest-scoring foods in our database.
Flaxseed for omega-3s. Blue Buffalo includes flaxseed as a plant-based source of omega-3 fatty acids, supporting skin and coat health from a whole-food source rather than a synthetic additive. Shop on Amazon →
Where Royal Canin holds its own
Glucosamine and chondroitin for joint health. This is Royal Canin's genuine advantage. Maine Coons are the largest domestic cat breed, regularly reaching 15-25 pounds, and their joints take more stress than a typical cat's. RC includes both glucosamine and chondroitin sulfate — the two most studied joint support compounds — directly in the formula. Blue Buffalo does not.
Psyllium seed husk for hairballs. Maine Coons have long, dense coats that produce significant hairballs. Psyllium is a soluble fiber that helps move ingested hair through the digestive tract, and its inclusion shows RC's breed-specific research at work.
Green tea extract antioxidant. A natural antioxidant source that provides polyphenols for cellular health. It's a small addition, but a thoughtful one compared to synthetic preservatives.
Breed-specific kibble size. RC designs their Maine Coon kibble in a larger shape to encourage chewing rather than gulping — a practical consideration for a breed prone to eating too fast. Shop on Amazon →
The bottom line
Blue Buffalo is the better food overall. Its ingredient foundation — deboned chicken, quality grains, no corn or soy — earns it a B grade that Royal Canin's by-product-and-corn formula can't match. The 18-point gap reflects a real difference in ingredient quality, not a technicality.
That said, Royal Canin's joint supplements are genuinely valuable for Maine Coon owners. Large-breed cats face real joint stress, and glucosamine plus chondroitin are well-supported by research. Our recommendation: feed Blue Buffalo for the superior base nutrition, and add a standalone glucosamine supplement if joint health is a concern. You'll get better protein, better grains, and the joint support — without accepting RC's lower ingredient quality as the trade-off.
Read our full reviews of Royal Canin Maine Coon and Blue Buffalo Cat for the complete ingredient breakdowns.