Deciphering Pet Food Labels

Brightly colored bags and cans with tempting photos of food line the shelves at the local pet store. The labels show delicious-looking food, happy cats and dogs, and words pledging “ All Natural,” “Grain Free,” and “Human Grade” among a vast array of other marketing terms. But what do these words actually mean in the world of pet food? Not all items or wording that are put in labels have regulated definitions. Some words or descriptions are marketing tools with no regulated definitions. Let's look into some examples:


The term “Natural” has been legally defined by AAFCO, and means that all ingredients are “natural” and nothing else has been added in. There are no artificial preservatives. Manufacturers have to meet the full definition set down by AAFCO: A feed or ingredient derived solely from plant, animal or mined sources either in its unprocessed state or having been subject to physical processing, heat processing, rendering, purification, extraction, hydrolysis, enzymolysis, or fermentation, but not having been produced by or subject to a chemically synthetic process and not containing any additives or processing aids that are chemically synthetic except in the amounts as may occur unavoidably in good manufacturing practices.

Companies can add more than plant, animal, and mined products to their foods and get away with having “Natural” printed on the labels thanks to the part of the regulation that allows the term “Natural” to be used to describe a specific ingredient, provided that the term refers only to that ingredient and not the product as a whole. For example, Charles’s Dog Treats with Natural Apple Flavor. The treat can be made with entirely synthetic food, but since there is a “natural” flavor (not an actual apple piece), the term can be used.

“Holistic” has not been legally defined by AAFCO. Holistic means to treat the body as a whole and take in account more than just the disease process. Because the term it is not legally defined, there is no way to tell what it means in relation to ingredients in the food.

“Organic” is legally defined in human food by the USDA. The ingredients in the food that are farmed will contain no pesticides or controls for at least 5 years to be considered organic. It will have the USDA seal on it.Pet food companies follow the same rules set by the USDA for human organic foods even though there is not a legal definition in the pet food world. The National Organic Standards Board ( NOSB) recommended in 2004 that a task force be formed to develop labeling standards for organic pet foods, but so far no regulation exists. AAFCO recommends that pet foods should not use “Organic” on their labels, but a company can legally use the term in their company name since there is no regulation on pet food company names. “Natural” and “Organic” are not interchangeable words.


Many times you may see “New” or “New and Improved” on a pet food label. This description is allowed for only 6 months after the introduction of the food. Flavor descriptions such as “Tastes Great” or “Improved Flavor” are marketing tools that have no regulation or definition.

“Human Grade” and “Human Quality” have no legal definition. Because there is no legal definition and it is hard to know what the manufacturers had in mind when using the term, “Human Grade” is a term that is not allowed on pet food labels but can be used in advertising and websites.
“Clinically Proven” is defined by AAFCO. A pet food product claiming that it is “proven” to help a certain condition must have scientific evidence to back it up. This means the product was tested on animals and there is evidence and research to back the claim.


In many pet foods “less,” “low,” or “reduced calorie” are used for pets needing to lose weight or for weight management. A true light food, which meets the criteria set forth by AAFCO, will be labeled “light”, “lite” or “low calories”. For dogs, there must not be more than 3100 kcal/kg in dry food. For cats, there must not be more than 3250 kcal/kg in dry food. Pet foods are not required to contain a calorie statement on the food label. It is voluntary for the company to add the number of calories per cup or can to the label EXCEPT if the label claims it is “light”, “low calorie”, or “reduced calories.” Foods labeled as “Less” or “reduced calories” does not have to abide by the “light” or “low calories” guidelines. Therefore a food can have twice as many calories as a pet may need and may not help the pet lose weight. “Less” or “Reduced calories” cannot just be printed on a label rather it must say Food X is x% lower in calories than Food Y (“Chuck's Reduced Calorie formula has 20% less calories than Chuck's Chunky Chunks”).
“Lean” or “Low Fat” are terms defined by AAFCO. The AAFCO Nutrient Profile requires a minimum of 5% crude fat in adult dog food to maintain weight and health in adult dogs. The regulation allows low fat dog foods to contain almost double that amount in dry food. In wet food, when adjusting the dry matter basis, foods can contain up to 18% fat. “Low fat” food can have more fat than what is recommended for growth, so if a pet needs to be on a truly restricted fat food, commercial diets are probably not the answer. The terms “Less Fat” or “Reduced Fat” can be used on a label but only when in comparison to a previous formulation of another food. There is no regulation on the terms “Weight Management” or “Weight Control” on pet food labels. Advertising can twist these terms into implying that the food is low in calories, but they do not have to follow the AAFCO guidelines for a truly low calorie diet.


If you look around the grocery store lately, you will see “gluten free” stamped on more and more food labels. While celiac disease and gluten intolerance are known health problems in humans, gluten intolerance is actually a fairly rare occurrence in dogs and cats, and is mostly limited to genetic gluten sensitivity in Irish Setters. Yet there are an increasing number of “gluten free” pet foods on the market. Corn and rice are the two most common grains used in pet foods, and both of them are gluten free, so it is easy for manufacturers to apply this label without any changes to their formulas. The term “gluten free” is not defined by AAFCO for pet foods, and studies have found that due to cross contamination in the field, during harvest, and during manufacturing, even foods that are formulated to be gluten-free actually contain glutens.
“Grain free” pet diets are also becoming more common. This is another term that is not regulated by AAFCO, and can have several meanings. The “grain free” designation may imply that the diet is low in carbohydrates, but many of these diets substitute other carbohydrate sources such as potato or tapioca for grains. These products actually have lower fiber and a higher glycemic index than whole grains, and are higher in carbohydrates than grains would be. Many grain free diets that do not contain tapioca or potato, and are lower carbohydrates, may make up the calorie difference with fat rather than protein.
Cats, especially those who are overweight or diabetic, can benefit from a reduced carbohydrate diet. Cats are true carnivores, and their gastrointestinal tracts and metabolism are not designed to process carbohydrates the way more omnivorous animals like dogs and humans can. An excellent resource for carbohydrate levels in a variety of commercial cat foods is: Your veterinarian can help determine if your cat should be on a low-carb diet and how best to achieve this goal.


The nutritional requirements for dogs and cats are very different than ours. A vegan or vegetarian diet can be suitable for us but can be grossly deficient where dogs and cats are concerned. Formulating a pet food to meet all the nutritional requirements set by AAFCO can be a difficult and costly task when only using ingredients that meet the requirements of a vegan or vegetarian diet. If you look at the physiology of cats and dogs compared to us, their teeth are designed for a diet consisting largely of animal tissue. The intestinal tracts of dogs and cats are shorter then ours, and are not designed to accommodate diets with a large amount of plant material.
Dogs are considered to be omnivores (meat and plant eaters), but their protein and calcium needs are much higher than those for humans. These nutrients are most easily provided through animal-derived ingredients. Some plants, such as soy, are high in protein, but the amino acids within the protein are not as balanced as they are for most animal-source ingredients. Dogs and cats also need a dietary source of vitamin B12, a substance not found in most plants. All animals "need" this vitamin, but plant-eating animals such as cattle and sheep can make their own through the action of bacteria in their gastrointestinal tracts, provided there are adequate amounts of the mineral cobalt in the diet (which is found in plants). Because dogs' diet is varied, a vegetarian diet than includes eggs, milk and other animal products can be fed. Vegan diets do not contain any animal products.
Cats are true carnivores, and have very strict dietary requirements which makes it more challenging to make sure they get the nutrients they need. For example, cats cannot convert the beta-carotene in plants such as carrots and dark green vegetables into vitamin A. They require "pre-formed" vitamin A, such as found in liver and fish oils. Cats also need dietary sources of taurine (an amino acid-like nutrient) and arachidonic acid (an essential fatty acid), both of which are found in appreciable levels only in animal tissues. Cats who are fed a vegetarian or vegan diet WILL develop severe nutritional deficiencies.


The most controversial and widely debated topic in pet nutrition is probably the topic of raw diets. Many veterinarians, the FDA and the AVMA are opposed to feeding raw meat to pets due to several health risks posed to pets and people. There is a lack of published research showing the benefits of raw diets, although there is anecdotal evidence that raw diets have been beneficial to some pets. While raw food has become a very popular type of diet in recent years, there are some definite concerns.

The American Veterinary Medical Association recently passed the following resolution:

Raw or Undercooked Animal-Source Protein in Cat and Dog Diets

The AVMA discourages the feeding to cats and dogs of any animal-source protein that has not first been subjected to a process to eliminate pathogens because of the risk of illness to cats and dogs as well as humans. Cooking or pasteurization through the application of heat until the protein reaches an internal temperature adequate to destroy pathogenic organisms has been the traditional method used to eliminate pathogens in animal‐source protein, although the AVMA recognizes that newer technologies and other methods such as irradiation are constantly being developed and implemented.
Animal-source proteins of concern include beef, pork, poultry, fish, and other meat from domesticated or wild animals as well as milk* and eggs. Several studies reported in peer-reviewed scientific journals have demonstrated that raw or undercooked animal‐source protein may be contaminated with a variety of pathogenic organisms, including Salmonella spp, Campylobacter spp, Clostridium spp, Escherichia coli, Listeria monocytogenes, and enterotoxigenic Staphylococcus aureus. Cats and dogs may develop foodborne illness after being fed animal‐source protein contaminated with these organisms if adequate steps are not taken to eliminate pathogens; secondary transmission of these pathogens to humans (eg, pet owners) has also been reported. Cats and dogs can develop subclinical infections with these organisms but still pose a risk to livestock, other nonhuman animals, and humans, especially children, older persons, and immunocompromised individuals.
To mitigate public health risks associated with feeding inadequately treated animal-source protein to cats and dogs, the AVMA recommends the following:

  • Avoid feeding inadequately treated animal-source protein to cats and dogs
  • Restrict cats’ and dogs’ access to carrion and animal carcasses (eg, while hunting)
  • Provide fresh, clean, nutritionally balanced and complete commercially prepared or home-cooked food to cats and dogs, and dispose of uneaten food at least daily
  • Practice personal hygiene (eg, handwashing) before and after feeding cats and dogs, providing treats, cleaning pet dishes, and disposing of uneaten food

The AVMA recognizes that some people prefer to feed raw or undercooked animal--‐source protein to their pets. The AVMA recommends that veterinarians inform pet owners of potential risks and educate them on how to best mitigate the risk of pathogen exposure in both handling the food and in managing pets consuming undercooked or raw animal-source protein diets.
* The recommendation not to feed unpasteurized milk to animals does not preclude the feeding of unpasteurized same-species milk to unweaned juvenile animals.”

The biggest concern about raw diets is the human health aspect of feeding and handling raw diets. While the pet owner has control over the ingredients that go into the diet, there is a lack of control over the safety of commercially available meat sources. Consumer Reports recently found that a very high percentage of chicken (over 80%) intended for human consumption, (some of it labeled organic) was contaminated with Campylobacter, while approximately 15% of the samples were contaminated with Salmonella (Consumer Reports, Jan 2007). Commercially available pet diets are not exempt from these issues; studies have demonstrated the presence of pathogenic bacteria in samples of several commercially available raw food diets (Freeman and Michel 2001, Strohmeyer et al. 2006, Weese et al. 2005). The principal behind feeding raw diets is that the nutrients remain in the more natural state, and that nutrients are not lost through the cooking process. Unfortunately, contaminants and bacteria on the meat are also not destroyed as they would be through cooking.  Another source of contamination comes from the feces of the pet. It has been shown that bacteria consumed through raw pet diets may be shed by the animal for 7-11 days after consumption. This poses a risk in cleaning up after the pet and the potential for small children to come in contact with fecal matter containing bacteria.

There are other concerns regarding raw diets. The first is the nutritional concern related to long-term feeding of homemade diets. It can be time consuming and difficult to balance a raw or homemade diet, and nutritional deficiencies, especially in vitamins and minerals, are a significant possibility. Some nutritional deficiencies take many months to show up and you may not see the problems with feeding a particular diet until the animal has been eating it for months or years. Working with a veterinarian or animal nutritionist can help provide the correct amount of balance in a homemade diet. Raw diets are not recommended for puppies due to the concern for lack of correct nutrition for growth, and the potential for structural damage to the skeleton over time. Also, ingestion of bones can cause choking, intestinal blockage or perforations, and chipped or broken teeth.

Homemade and raw diets can be time consuming to make, require a lot of storage space for ingredients, and ingredients can be costly. Some boarding facilities and hotels charge extra or do not have the space for adequate storage of food.

If you are interested in feeding a raw diet, please talk to your veterinarian at Animal Hospital of North Asheville about doing so in a way that is safe and nutritionally appropriate for your pet.

Additional resources regarding raw food diets can be found here: