Key Takeaways
- Grain-free diets are not inherently healthier for most dogs or cats.
- Raw feeding carries real food-safety risks that commercial processing is designed to minimize.
- By-products in pet food can be nutritious ingredients — not just filler.
- Cheap versus expensive pet food is less important than AAFCO nutritional completeness statements.
- Always consult your veterinarian before making major changes to your pet's diet.
Why Pet Nutrition Myths Spread So Easily
Social media, well-meaning friends, and persuasive product marketing all contribute to a steady stream of nutrition claims about what pets should — or absolutely shouldn't — eat. The problem is that these claims often get repeated without any reference to veterinary science or regulatory standards. Meanwhile, the bar for what counts as 'evidence' online can be a single anecdote or an influencer's enthusiastic endorsement.
Understanding a few core facts about how pet food is regulated and studied makes it much easier to filter out noise. In the United States, the Association of American Feed Control Officials (AAFCO) sets model nutritional standards for pet food, and FDA oversight applies to labeling and safety claims. When a myth contradicts both regulatory guidance and published veterinary research, that's a strong signal to pause before acting on it. The Pet Health & Wellness hub has additional resources for keeping your pet healthy with decisions grounded in evidence.
Myth
Grain-free pet food is healthier because dogs and cats evolved to eat only meat.
Fact
Grain-free does not mean nutritionally superior, and for dogs, some grain-free diets have been linked to a possible increased risk of dilated cardiomyopathy (DCM).
The idea that grains are harmful fillers ignores how pet nutrition actually works. Dogs are omnivores with digestive systems well-adapted to processing carbohydrates, including grains. Cats are obligate carnivores, but grains at appropriate levels in a complete diet do not harm them. The FDA investigated a potential association between grain-free diets — particularly those high in legumes and potatoes — and DCM in dogs. While the causal link is still being studied, veterinary cardiologists have flagged the pattern as a concern worth taking seriously. For most pets without a diagnosed grain allergy or intolerance, a grain-inclusive diet that meets AAFCO nutritional standards is a sound, evidence-supported choice.
Myth
Raw diets are more natural and therefore safer and more nutritious than cooked or processed food.
Fact
Raw pet food carries measurable food-safety risks — including Salmonella and Listeria — that can affect both animals and the humans handling the food.
The appeal of raw feeding is understandable: 'natural' sounds better than 'processed.' But multiple studies, including research reviewed by the FDA and CDC, have documented that raw meat diets for pets are significantly more likely to be contaminated with pathogenic bacteria than commercially cooked alternatives. Puppies, kittens, elderly pets, immunocompromised animals, and households with young children or immunocompromised people face the greatest risk. Cooking and processing eliminate most of these pathogens. If you're considering raw feeding, discuss it thoroughly with your veterinarian and follow rigorous food-handling protocols — it is not a risk-free option.
Myth
Meat 'by-products' in pet food are low-quality scraps with no nutritional value.
Fact
By-products like organ meats are often nutrient-dense and are a legitimate protein and vitamin source in many formulations.
The word 'by-product' triggers understandable skepticism, but in pet food regulation, it has a specific meaning. According to the Association of American Feed Control Officials (AAFCO), poultry by-product meal includes organs such as liver, lungs, and kidneys — all of which are nutritionally rich. Organ meats provide protein, fat, and key vitamins including A and B12. The inclusion of by-products does not automatically indicate poor quality; what matters most is whether the overall formulation meets AAFCO standards for complete and balanced nutrition. You can learn more about reading those label statements in our plain-language label guide.
Myth
The first ingredient on the label tells you everything about food quality.
Fact
Ingredient order reflects pre-cooking weight, not post-processing nutritional contribution — so a single ingredient doesn't capture the full picture.
Ingredient lists are organized by weight before processing. Fresh chicken, for example, is roughly 70% water, so after cooking it contributes far less protein by weight than it appears to at first glance. A named meat meal (like chicken meal) listed third may actually provide more protein than fresh meat listed first. This is one reason reading the guaranteed analysis panel alongside AAFCO nutritional adequacy statements gives you a more complete picture. Our article on reading pet food labels without getting lost in the fine print explains exactly how to do this step by step.
Myth
More expensive pet food is always better for your pet.
Fact
Price does not reliably predict nutritional quality; what matters is whether the food meets AAFCO standards for your pet's life stage.
Premium pricing in pet food often reflects marketing, packaging, or ingredient sourcing philosophy rather than measurable health outcomes. A mid-priced kibble with an AAFCO 'complete and balanced' statement for your pet's life stage may be nutritionally equivalent — or even superior — to a costly boutique option that lacks rigorous feeding trials. Budget-conscious pet owners can feed their animals well by focusing on that AAFCO statement and, where possible, choosing brands that conduct feeding trials rather than relying solely on formulation-based standards.
What the Evidence Actually Shows
The five myths addressed above share a common thread: they each sound plausible on the surface but fall apart under scrutiny. Grain-free and raw diets have genuine followings, but both carry trade-offs that marketing materials rarely mention. Ingredient anxiety around by-products and label placement leads many owners to pay more for food that isn't demonstrably better for their pet.
This Is General Information, Not Veterinary Advice
The content in this article is for educational purposes only and does not constitute veterinary or medical advice. Every pet has individual health needs. Before changing your pet's diet — especially if they have existing health conditions — consult a licensed veterinarian.
The most reliable approach is to look for AAFCO's 'complete and balanced' language on packaging, choose a life-stage-appropriate formulation, and check in with your veterinarian at routine visits. If your pet has specific health concerns — digestive issues, food sensitivities, weight management needs — those conversations become even more important. For a broader look at how widespread nutrition myths affect both humans and pets, see our article on nutrition myths most Americans still believe. And if you're weighing wet versus dry food options, our comparison of wet food vs. dry kibble covers the practical trade-offs clearly.
~77%
Pet owners influenced by online sources
A survey by the American Pet Products Association found a large majority of pet owners report turning to online content when researching pet food decisions.
16+
Dog breeds flagged in FDA DCM investigation
The FDA's ongoing investigation into diet-associated dilated cardiomyopathy identified more than 16 breeds among reported cases, many eating grain-free diets.
~21%
Raw pet food samples testing positive for Salmonella
FDA testing of commercially available raw pet food found Salmonella contamination in roughly one in five samples examined.
This article is for general informational and educational purposes only. It is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before making changes to your pet's diet or care routine.