Choosing a food for your cat can seem daunting. There are more brands and styles of cat food on the market than ever before. With so many brands out there, it can seem near impossible to pick the best one for your cat. What are things to look for in a cat food? How can you know you’re picking a healthy option?
Some healthy ingredients to look for:
- A protein source other than meat
- Ingredients that are low on starch
- Ingredients recommended by the Association of American Feed Control Officers (AAFCO)
Basic Nutritional Needs for Cats
Cats are considered to be obligate carnivores. This means they require animal protein in their diet in order to obtain adequate nutrition because they can't efficiently synthesize the amino acid taurine from other nutrients. Instead, they need to get it from their diet. Taurine is only found in animal proteins, so it is unhealthy for a cat to be fed a vegetarian diet. A cat fed a diet deficient in taurine can develop a serious heart muscle disease called dilated cardiomyopathy (DCM). In fact, DCM used to be one of the most commonly diagnoses acquired heart diseases in cats until researchers discovered the link between taurine deficiency and DCM in cats. A cat fed a taurine deficient diet isn't just at risk of DCM, though. They can also develop central retinal degeneration and reproductive failure.
Cat Food Labeling
The Association of American Feed Control Officers (AAFCO) is an organization of animal feed specialists who make recommendations for ideal diet compositions for different animals. AAFCO provides recommendations for diets to meet minimum nutrient compositions to avoid risks of malnutrition but does not regulate pet food. Cat food—and pet food in general—are regulated by the Food & Drug Administration (FDA). The FDA enforces food safety. If a manufacturer has chosen to AAFCO recommendations, its bags and cans of cat food will have an AAFCO statement, sometimes called a nutritional adequacy statement, on them. This statement lets the pet owner know that the diet is complete and balanced for the stated life stage. Complete meaning all the nutrients required for the life stage are present. Balanced meaning all the nutrients are in perfect balance and ratio so as to not provide too little or too much of any nutrient.
Current life stages recognized by AAFCO are growth/kittens, adult/maintenance, and all life stages. The FDA regulates what nutritional requirements are needed for these life stages based on the recommendations of AAFCO.
The AAFCO statement will also let you know whether the diet was formulated or whether it underwent feeding trials. Formulated diets are species-specific nutrient content requirements (rather than ingredients), that include minimum needs to provide adequate nutrition and development in an animal, and what is needed to avoid malnutrition.
Feeding trials are clinical studies that demonstrate the effects of a diet on a set group of animals, and allow a pet food company to demonstrate the healthiness of a diet. This is important because, while multiple proteins may be sources for the same nutrient, that nutrient may be absorbed differently from one protein to another. Additionally, different ingredients may interact differently once broken down into their nutrients, which can also effect how a nutrient is actually absorbed by the cat.
A Word on Ingredients
In recent years a lot of pet food companies have utilized reading the ingredients in their marketing as a way to prove their wholesomeness to pet owners. The ingredients of a pet food will be listed in descending order of weight, with the first ingredient listed weighing the most and the last weighing the least. This is why a lot of pet foods will have a meat source listed as the first ingredient, because whole meats contain a lot of moisture, which adds weight. Some companies will tell you to steer clear of "meat meal," "chicken meal," etc. but the word "meal" just means all moisture has been removed from the meat. This can actually make it a more protein-dense ingredient than the whole source ingredient and may also contain other nutrients, such as glucosamine, to help improve joint health.
Although a food with chicken as the first ingredient may look like a healthy option, if the next several ingredients are more starch-related and less animal protein-related, that might actually be less nutritionally dense than a pet food that has different protein sources. Meat meal and chicken meal have comparable levels of digestibility when compared to one another.
Pet food companies are also allowed to label a whole source ingredient into separate things. For instance, instead of saying "corn," the label may read "corn meal," "corn gluten meal," etc. Pet food companies do this for they same reason they may leave a protein source whole and not as a meal. Since the ingredients are listed by weight, "corn" as a whole ingredient may end up higher up on the ingredient list than a pet food company may like. By breaking up an ingredient, the individual items (i.e. ground corn, corn meal, flaked corn) can appear lower on the ingredient list. This is also why some pet food ingredient labels may list a derivative of corn or other starches multiple times.
Canned Food vs. Kibble
For a long time, and still to this day, there is a debate about whether you should feed a cat dry kibble or a canned diet. Dry cat food is relatively inexpensive and easily allows for ‘free choice’ feeding. Dry food can have a long shelf life but once opened should still be kept in an airtight container and used within a month or so of opening. The vitamins and minerals in dry food can begin to degrade if the food is stored open, even in an airtight container, for an extended period of time. This will make it no longer complete or balanced because the vitamins and minerals are no longer able to be absorbed by the cat.
Dry food that has been opened for an extended period can also spoil as the fats in the food can quickly turn rancid.
Dry food is much more cost effective than canned food, proponents of canned food are concerned about more unnecessary carbohydrates being in dry food than canned food. However, going back to what we know about pet food labeling, if the dry food is labeled to be ‘complete and balanced’ that statement alone trumps any concern about too many carbohydrates in the diet. Again, this is because a complete and balanced diet will have all of the nutrients a cat requires and all of them in proper proportion to one another.
Canned food has a moisture content of 75%. This makes it a great source of water for cats, but it is debatable how much this helps, as some cats may reduce their water intake when eating canned food. Some feel that this increase water content can be beneficial for those cats that may not drink enough, especially when struggling with renal disease or bladder inflammation, where the higher water intake can better flush out the urinary tract. Uneaten canned food should be picked up after a few hours. Additionally, canned food does not provide a hard surface on which to chew, which may affect dental health as well.
Grain Free vs. Grain Containing
Grain-free diets have been around for over a decade at this point and a popular fad which has proven to have significant health risks for pets. They are marketed as 'premium' and 'holistic' diets for pets, although it should be noted AAFCO doesn't regulateDCM either of those terms, so they truly mean whatever the pet food company wants you to believe they mean. Increased numbers of pets developing DCM have been observed with pets who have been fed grain-free, boutique, or exotic diets. While diet related DCM has been know for some time, in diets deficient in taurine or protein, in recent years there has been a link established between grain free diets and DCM. While most of the research centers around diet-related DCM in dogs, there have been some cases in cats reported as well.
Raw diets are also gaining popularity in recent years. These can come as frozen raw diets, freeze dried raw diets, and even raw-coated kibble. Proponents of raw feeding tout numerous benefits. Unfortunately, the benefits of feeding a raw diet has not been scientifically documented yet. On the other hand, the risks pathogenic bacterial infections from the raw diet have been.
Choosing the right diet for your cat can be daunting. Now, more than ever, there is an overabundance in both brand and type of cat food. Choosing the healthiest one can seem near impossible, but there are things to look for to help you differentiate a healthier diet from other, not so healthy diets. Certain health requirements also have more strict dietary needs. Consider looking for diets with an AAFCO statement and seeking advise from veterinary professionals.
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Rishniw, M. AAFCO Pet Food Labeling. Veterinary Partner. 2018. Accessed June 8, 2022
Funaba M, Oka Y, Kobayashi S, et al. Evaluation of meat meal, chicken meal, and corn gluten meal as dietary sources of protein in dry cat food. Can J Vet Res. 2005;69(4),299-304
Freeman LM, Stern JA, Fries R, Adin DB, Rush JE. Diet-associated dilated cardiomyopathy in dogs: what do we know? Journal of the American Veterinary Medical Association. 2018;253(11), 1390-1394, doi:10.2460/javma.253.11.1390