FOOD FOR THOUGHT: Pet Food Labels Part 1

November 21, 2019

The information on your cat food label is misleading and does not give you an adequate representation of the quality of the food you just purchased. You cannot (and should not) look at a food label and conclude that one diet is better than another diet. Think of a pet food label as more of a legal document than actually informing you about the nutrition in the diet. The goal here is not to outline a comprehensive breakdown on the “ins and outs” of a pet food label. Instead, we hope to provide a few examples to highlight the fact that reading a pet food label is not as easy as it sounds and often times is misleading.

A pet food label is a legal document,
not a nutritional profile.

Ingredient List: The list of ingredients does not tell you about the ingredient quality, ingredient digestibility, nutrient composition of the ingredient, or bioavailability of the nutrients within the ingredient. You cannot determine if a diet is better than another diet simply by looking at the ingredient list. Ingredients are listed in order of their weight with the heaviest ingredient listed first and the lightest ingredient listed last. One “trick” pet food marketers use is splitting ingredients, where different forms of the same ingredient are listed separately. Since these different forms weigh less, they can be moved down the ingredient list and give the appearance that the diet does not contain a lot of said ingredient. When you add all of the different forms up, they may actually constitute are large portion of the diet. Similarly, meat is 70-80% water and is generally one of the first ingredients in many “premium diets” because it weighs more. This does not mean that meat composes a higher percentage of the diet. Once you remove water from meat, the meat ingredient moves toward to the bottom of the list. Ingredients lower on the list, especially if ingredient splitting has occurred, may still compose a higher percentage of the diet than the meat ingredient listed first. As mentioned above, the ingredient does not indicate whether your cat can pull the required nutrients and use it from said ingredient. Cats can pull more protein from chicken meat meal than they can from a chicken breast ingredient listed first. Meat as the first ingredient is more marketing than science.

It is easy to manipulate the ingredient list
so meat is the first ingredient.


Guaranteed Analysis Percentages: There are only four nutrients that are required on a pet food label: (1) minimum crude protein, (2) minimum crude fat, (3) maximum crude fiber and (4) maximum moisture. These percentages are simply minimum or maximums, not the actual amount of said nutrient. For example, crude protein is an estimate of the quantity of the protein. Pet food companies are not required to publish the actual percentage, only the guaranteed minimums or maximums. It also says nothing about the amino acid content, digestibility or bioavailability of that protein. There are many more nutrients required by your cat that are not listed, making this list essentially useless.

Guaranteed analysis percentages are just minimums
and maximums, not the actual nutrient concentration.

Carbohydrates: These do not have to be included on the label. They are also not measured in the pet food. To get the percentage of carbohydrate in the diet, use this calculation: 100 – crude protein (%) – crude fat (%) – crude fiber (%) – moisture (%) – ash (or magnesium %). This percentage of carbohydrates (a very rough estimate) on the label does not distinguish between the different types of carbohydrates. It also does not determine how many calories come from carbohydrates. You have to take into account that the protein and fat percentages are minimums. The carbohydrate percentage may actually be lower if there is in fact more protein and fat in the diet.

AAFCO: The Association of American Feed Control Officials organization has both feeding trials and nutritional profiles that may be on the pet food label. During the 26 week feeding trial, cats are fed the specific diet under specific guidelines outlined by AAFCO. A veterinarian examines the cat before and after the trial and blood samples are taken at the end of the trial. The AAFCO feeding trial leaves much to be desired and it will not “pick up” all problems during the 26 week time frame. Nonetheless, I still recommend companies and diets that have undergone a feeding trial. The AAFCO nutrient profile means a diet has met the standard minimal and maximum nutrient requirements set forth by AAFCO. Again, a nutrient profile has limitations and the profile does not mean the nutrient from an ingredient will be absorbed and used by your cat. An example is using a carrot (an ingredient) to provide your cat with Vitamin A (a nutrient). The nutrient profile may say that there is adequate Vitamin A in your cat’s diet thanks to the carrot ingredient. The nutrient profile does not say that cats can pull very little, if any, Vitamin A from carrots. Even though the nutrient profile says the diet has enough Vitamin A, if the Vitamin A is only coming from carrots, your cat will be Vitamin A deficient. I still recommend diets with an AAFCO nutrient profile over diets that do not contain one.

Choose diets that have undergone an AAFCO
feeding trial and/or nutrient profile.

Dry Matter Basis: When you remove all of the moisture from canned and dry diets, you have the actual percentages of the ingredients in the diet. Dry matter percentages of nutrients are the only way to compare diets and these are not reported on the pet food label. You either have to find the dry matter (DM) percentages online or call the company. If you look at the label and notice the phrase “as fed,” the percentages given on the label were calculated directly without taking into account the water content of the diet. Those percentage may change when you account for the water in the diet (dry 6-10% water, canned 70-80% water).

Complete And Balanced: This phrase means that the diet provides all of the essential nutrition (required nutrients in the necessary ratios…as far as we know) for the specific life stage of your kitten/cat and does not require additional nutritional supplementation.

You should feed a diet that is labeled
“complete and balanced.”


Bioavailability: The proportion of nutrients (from the ingredients) that is available to use by your cat during digestion. Bioavailability is not reported on your cat’s food label. This is another reason why ingredients do not matter. You may have a desired ingredient in your cat food, but if your cat cannot process that ingredient to use the nutrient(s) contained within the ingredient, there is little benefit to your cat eating that ingredient. You cannot determine the bioavailability characteristics of an ingredient by reading the food label.

You cannot look at a pet food label and make a rational decision about the quality of the diet.

I’m sure many of you are thinking “Thanks for making this even more confusing!” Unfortunately, this is the world we live in. You are much better served by looking at the experience of the manufacturer, reputation of the manufacturer and the investment in AAFCO feeding trials (or nutrient profiles) when choosing a diet than you are at looking at the label. Another great resource is the veterinarian (i.e. the person you pay to talk about your cat, who has undergone 8 years of schooling and has a personal interest in the well-being of your cat). I generally do not have brand loyalty but recommend choosing a diet from the big pet food companies. These companies employ veterinary nutritionists to formulate their diets and are generally doing more testing to ensure a diet is complete and balanced. When clients ask about a specific diet, we do have some general recommendations. There are some diets we see problems with over and over and do not recommend feeding to your cat. Alternatively, some companies are too new to give any opinions about as we do not have a lot of experience with these diets. The veterinarian is a better resource than the pet store employee or someone recommending nutrition on Google.

Next month we will discuss specific phrases on pet food labels and what they actually mean in Part 2 of FOOD FOR THOUGHT: Food Labels (& the headaches they give us).


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