Navigating pet nutrition generates a lot of questions, many of which get conflicting answers depending on who you ask. Below are straightforward, evidence-based responses to the questions pet owners raise most often.
Ingredients are listed in descending order by weight before processing. This means the first ingredient contributes the most to the formula by mass. However, there is an important nuance: fresh meat contains roughly 70% water, so “chicken” listed first may contribute less actual protein than “chicken meal” listed second, because meal has already had the water removed. Look at the first five ingredients to get a realistic picture of what makes up the bulk of the food. Avoid products where the first named protein does not appear until the third or fourth position.
The term “human-grade” has a specific legal definition under AAFCO guidelines. For a pet food to be labeled human-grade, every ingredient must be human-edible and the product must be manufactured in a facility that meets human food production standards. Many brands use phrases like “made with human-grade ingredients,” which is a meaningfully different (and less regulated) claim. If the product does not explicitly state the finished product is human-grade, assume it is produced under standard pet food manufacturing conditions.
In 2018, the FDA began investigating a potential link between grain-free diets and dilated cardiomyopathy (DCM) in dogs. The concern centered not on the absence of grains but on the high concentration of legumes (peas, lentils, chickpeas) and potatoes used as replacements. As of the latest updates, the FDA has not issued a formal finding of causation, but the correlation was concerning enough that many veterinary cardiologists now recommend against grain-free formulas unless a dog has a diagnosed grain allergy. If your dog tolerates grains, there is no established nutritional reason to avoid them.
Feeding guidelines printed on pet food packaging are starting estimates, not precise prescriptions. They are based on average activity levels and may not match your individual pet’s metabolism. Start with the manufacturer’s recommendation for your pet’s weight, then adjust based on body condition over two to four weeks. You should be able to feel your pet’s ribs without pressing hard, and there should be a visible waist when viewed from above. Your veterinarian can help you determine an ideal caloric target, especially for pets that need to gain or lose weight.
Not necessarily. “By-products” in pet food refer to parts of an animal other than muscle meat: organs, blood, bone, and connective tissue. Many of these components are nutrient-dense. Liver, kidney, and heart are excellent sources of vitamins and minerals. The concern with by-products arises when the source animal is not specified (e.g., “meat by-products” rather than “chicken by-products”) or when by-products dominate the formula with minimal muscle meat. Named by-products from a single species are nutritionally legitimate ingredients.
Rotational feeding, switching between brands or protein sources periodically, can offer dietary variety and reduce the risk of developing sensitivities to a single protein. However, abrupt changes can cause digestive upset. If you choose to rotate, transition gradually over five to seven days by mixing increasing proportions of the new food with the old. Some pets with sensitive stomachs do better on a consistent diet, so observe your animal’s response and adjust accordingly.
If your pet eats a commercial food that meets AAFCO nutritional adequacy standards (look for the “complete and balanced” statement on the label), supplementation is generally unnecessary and can sometimes cause nutrient imbalances. The exceptions include pets on home-prepared diets (which almost always require supplementation), animals with specific medical conditions (joint disease, skin conditions, digestive disorders), and senior pets whose absorption efficiency has declined. Always consult your veterinarian before adding supplements to avoid overshooting safe intake levels for fat-soluble vitamins and minerals.
Under AAFCO definitions, “natural” means the product contains no chemically synthesized ingredients, with the exception of added vitamins, minerals, and trace nutrients. “Organic” is regulated by the USDA and requires that ingredients be produced without synthetic pesticides, fertilizers, antibiotics, or growth hormones. Organic pet food must meet the same USDA organic standards applied to human food. A product can be natural without being organic, and organic without being natural (if it contains synthetic vitamins). Neither term alone guarantees superior nutritional quality.
True food allergies in pets are less common than many owners assume. Symptoms typically include chronic itching (especially ears, paws, and rear end), recurrent ear infections, and gastrointestinal issues. The only reliable diagnostic method is an elimination diet trial: feeding a single novel protein and carbohydrate source (or a hydrolyzed protein diet) for eight to twelve weeks, then systematically reintroducing ingredients to identify the trigger. Blood tests marketed as food allergy panels have poor accuracy and are not considered reliable by veterinary dermatologists.
Homemade diets offer complete ingredient control and can be tailored to individual health needs. However, multiple studies have found that the vast majority of homemade pet food recipes, including those published in books and online by veterinarians, are nutritionally incomplete. If you choose to prepare your pet’s food at home, work with a board-certified veterinary nutritionist (DACVN) who can formulate a balanced recipe specific to your pet’s needs and prescribe the correct supplements to fill any nutritional gaps.