The dog food aisle is built on stories. Wolves on the packaging. "Ancestral diet" on the label. Marketing copy that whispers: your dog is a wild predator, trapped in a domestic body, and only meat — raw, primal, unprocessed — can set them free.
It's a powerful narrative. It's also wrong.
Here are five of the most persistent myths in canine nutrition — and what the science actually says about each one.
Myth No. 1
"Dogs are carnivores, not omnivores."
In 2013, a landmark study published in Nature — one of the world's most prestigious scientific journals — settled this debate at the genetic level. Researchers led by Erik Axelsson at Uppsala University compared the genomes of dogs and wolves and found that dogs have developed up to a 28-fold increase in AMY2B gene copies compared to wolves. AMY2B produces pancreatic amylase, the enzyme that digests starch. Each additional gene copy is associated with a 5.4% increase in amylase activity. The study identified changes in 10 genes related to starch digestion and fat metabolism, concluding that "adaptations allowing the early ancestors of modern dogs to thrive on a diet rich in starch constituted a crucial step in the early domestication of dogs." Dogs didn't just learn to eat alongside humans. They evolved to eat like them — including vegetables, grains, and fruits. Your dog isn't a wolf. They haven't been for 15,000 years.
28×
More starch-digesting genes in dogs vs. wolves
Myth No. 2
"Grain-free is always better."
There is no scientific evidence that grain-free diets are healthier for most dogs. The top canine food allergens aren't grains — they're beef, dairy, and chicken. Wheat ranks only fourth. More critically, the FDA began investigating a link between grain-free diets and dilated cardiomyopathy (DCM) in 2018. Of the 1,382 DCM cases reported, 91% involved grain-free products, 93% contained peas and/or lentils, and 42% contained potatoes. A 2025 prospective study in the Journal of Animal Science found that dogs on grain-free, legume-rich diets showed larger left ventricular diameters and reduced heart function. Tufts University's veterinary nutrition team warned in 2023: "The cause is not yet known but it hasn't gone away." Grains like white rice — a staple in Rhino Pet Plates meals — provide clean, easily digestible energy with a strong safety profile. The grain-free trend was built on marketing, not medicine.
Myth No. 3
"Raw food is the most natural, so it must be best."
The appeal of raw is intuitive: wolves eat raw, therefore dogs should too. But as we've established, dogs aren't wolves. And the risks are real. Raw animal products can harbor Salmonella, Listeria, Campylobacter, and E. coli, posing health risks to both dogs and their human families — especially children, the elderly, and immunocompromised individuals. The AVMA, FDA, and CDC all advise against raw meat-based diets. Meanwhile, very few of the claimed benefits (shinier coat, better digestion) are supported by published, peer-reviewed research. Lightly cooked fresh food delivers the same whole-food benefits — real meat, intact nutrients, identifiable ingredients — without the bacterial risk. It's not about being natural. It's about being smart.
Myth No. 4
"By-products are always bad."
This one is more nuanced. Named organ meats — chicken liver, beef kidney, turkey heart — are actually nutrient powerhouses. Liver is one of the richest natural sources of vitamin A, iron, and B vitamins. Heart is packed with taurine, an amino acid critical for cardiac health. These organs are considered delicacies in cuisines around the world. The problem isn't by-products themselves — it's unnamed, unspecified by-products ("animal by-product meal") where you can't verify the source species, the quality, or the processing conditions. The distinction matters. A named, single-source ingredient you can trace? That's good nutrition. A vague category label hiding unknown contents? That's where trust breaks down.
Myth No. 5
"Vegetables are filler. Dogs don't need them."
This myth flows directly from the "dogs are carnivores" misconception. In reality, vegetables provide nutrients that meat alone cannot. Sweet potato delivers beta-carotene (vitamin A precursor), complex fiber for gut health, and manganese for bone development. Broccoli contains sulforaphane, a compound with documented anti-cancer properties in mammalian studies, plus vitamin C and vitamin K. Carrots provide pectin — a prebiotic fiber that selectively feeds beneficial gut bacteria — along with biotin for coat health. Blueberries rank among the highest ORAC-value foods on earth (oxygen radical absorbance capacity), meaning they neutralize free radicals more effectively than almost any other food. A 2002 study of 125 aging beagles found that an antioxidant-enriched diet produced significant cognitive improvement within 30 days. Vegetables aren't filler. They're medicine the body recognizes.
Why Myths Persist
These myths endure because they're profitable. "Grain-free" creates a premium price point. "Ancestral" evokes emotional connection to wildness. "All-meat" sounds more generous than it is. The pet food industry spent decades — starting with the Pet Food Institute's 1964 advertising campaign — convincing Americans that only commercially prepared food was safe for dogs. The current wave of myths is the same playbook, inverted: now "natural" and "raw" and "wild" are the premium signals.
The truth doesn't fit on a label. Dogs evolved alongside humans. They thrive on balanced diets that include quality protein, complex carbohydrates, and whole vegetables. The best diet isn't the most "ancestral" or the most expensive or the most marketed. It's the one built from real ingredients, prepared with care, and informed by actual science.
That's not a myth. That's just a good meal.
Sources
- Axelsson, E. et al. (2013). "The genomic signature of dog domestication reveals adaptation to a starch-rich diet." Nature, 495, 360–364. nature.com
- Arendt, M. et al. (2014). "Amylase activity associated with AMY2B copy numbers." PMC
- Tufts University Petfoodology (2023). "Diet-Associated Dilated Cardiomyopathy Update." tufts.edu
- "Role of Diet as a Predisposing Factor for DCM." (2024). PMC
- American Kennel Club. "Dilated Cardiomyopathy in Dogs Update." akc.org
- Cotman, C.W. et al. (2002). "Brain aging in the canine: a diet enriched in antioxidants." Neurobiology of Aging. PubMed
- The Farmer's Dog. "The History of Commercial Pet Food." thefarmersdog.com