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How to Interpret Those Pesky Labels

As we begin to think more about what is healthy and not healthy for ourselves to eat, it is only natural that we start to think about this for our four-legged family members.  We, of course, want the best for them, too. There are so many choices available, with new options every day. And whom should we trust for recommendations? The breeder? Our friends? The sale’s person at the pet store? The advertisements of the pet food companies? A veterinarian? Everyone seems to have different opinions and words of advice.

We do know from research what nutrients (amino acids, fatty acids, vitamins, minerals, etc.) are essential to a dog and cat on a daily basis, but there are multiple ways to accomplish this. The sale and distribution of pet food in the United States is regulated by the Association of American Feed Control Officials, or AAFCO. This is a voluntary membership association of local, state, and federal agencies that regulates the sale and distribution of animal feed, including making sure that foods are labeled appropriately. But what most people don’t realize is that there is that there is no regulatory body to ensure that what is on the label is what is in the package. Many pet food companies have their foods made at a third-party processing plant, and there are variable protocols for how this equipment is cleaned (or not cleaned) between batches of food.

All pre-packaged food will have an AAFCO statement on it. If the label says “Formulated to meet the nutritional levels established by the AAFCO Food Nutrient Profiles,” this means that the food had a recipe formulated to include the required nutrients. This does not guarantee, however, that the nutrients are “bioavailable,” meaning that they can be digested and absorbed by your pet’s gastrointestinal tract instead of just passing through. If the label says “Animal feeding tests using AAFCO procedures substantiate that this food provides complete and balanced nutrition,” then studies have been done feeding the diet to animals, and it was found to provide the necessary nutrients as advertised. If the packaged food does not meet either of these standards, then it is labeled, “This product is intended for intermittent or supplemental feeding only.”

The label must include all of the ingredients in descending order based on quantity, and a minimum or maximum of the different types of nutrients including protein, fat, fiber, vitamins, minerals, and moisture. But as long as these basics are met, the amounts can vary substantially, including from bag to bag. It is also important to note that not all foods can be compared directly because most labels are written on an “as-fed” basis, not taking into account the moisture content. Two foods may list 15 percent protein, but if one food is 5 percent moisture and the other is 70 percent moisture, then the actual amount of protein in the food is quite different and must be compared on a “dry-matter” basis, factoring out the water component.

As for the individual ingredients, it is difficult to say if one protein source is better than another for an individual animal, though just like people with food allergies to shellfish or peanuts (or who have Celiac disease and there gluten sensitivity), proteins or certain grains can sometimes trigger gastrointestinal upset or itchy skin in some pets. We now know that eliminating all grains from pet food diets can predispose some pets to heart disease. We also know that as cats and dogs have been domesticated, they have lost some of the genes needed for digestion of raw foods. While there can be adverse reactions to mycotoxins or other preservatives in canned or kibble diets, there are a lot of dogs and cats that get sick associated with eating raw food diets, including infections with salmonella, E. coli, Listeria, and recently tuberculosis. Unfortunately, their people also get sick from handling raw foods or not realizing that their pets become asymptomatic carriers for these infections — not getting sick themselves but passing them on.

Many people choose to home cook for their pets, but how do you know that a recipe found on line is balanced and safe to feed long-term? Working with a veterinary nutritionist or similarly approved website such as can help ensure a healthy diet. When adding snacks to our pet’s meal plan, it is recommended to keep the calories less than 10 percent of their daily intake to ensure that they are still getting the balanced nutrition their diets provide. Making sure that our pets are not getting too many calories in a day is also important because, just like people, overweight pets are at increased risk for heart disease, liver disease, arthritis, and cancer. Lastly, don’t forget that some foods we eat on a regular basis can be quite toxic to dogs, including onions, garlic, grapes, raisins, chocolate, and macadamia nuts, and “chews,” including bones and raw-hides, that can fracture teeth, be choking hazards, or get stuck in the esophagus on the way down.

Pet parents seeking more information should discuss their pet’s nutritional needs with their veterinarian, a veterinary nutritionist, or internal medicine veterinarian. 

Jennifer Strasser, DVM, DACVIM (SAIM), practices veterinary medicine at SAGE Veterinary Centers. She earned an undergraduate degree from the University of New Mexico and her veterinary medicine degree from Colorado State University. She has completed internships in small animal medicine and surgery and a residency in internal medicine in which she is board certified. She enjoys the challenges of gastrointestinal, endocrine, and urinary tract diseases, and the diagnostic capabilities of endoscopy and ultrasound. When not practicing, she enjoys yoga, sailing, camping, skiing, and spending quality time with her family. She is the proud owner of two chocolate Labs, who also happen to be her favorite hiking companions. Learn more at

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Main article photo by: Courtesy of the California Historical Society