There are many options when it comes to selecting a food for your cat. These food options can be categorized in several ways, but the main groups are usually "conventional" and "alternative". While a conventional diet may be the best choice for most cats, there are some cats who might do better on an alternative diet, or instances where the pet owner prefers that way of feeding.
Ultimately, the most important consideration is whether the food selected is complete, balanced, and appropriate for the pet.
What is complete and balanced cat food?
As a minimum, cats have requirements for several essential nutrients that they must get from the food they eat. For conventional and alternative diets that are purchased from a retail location, the pet food label should be inspected for a nutritional adequacy, or AAFCO, statement.
This statement tells the consumer that the food has either undergone a feeding trial or has been formulated to meet the nutrient requirements for a given species and life stage according to the American Association of Feed Control Officials (AAFCO) requirements. The presence of this statement is not mandatory and, if absent, we cannot be sure whether a food is complete (contains all essential nutrients) and balanced (in the correct proportions).
"For conventional and alternative diets that are purchased from a retail location, the pet food label should be inspected for a nutritional adequacy, or AAFCO, statement."
These nutrients can come from a variety of ingredients and combinations, so in most instances, unless there is a food allergy, the ingredients are not as important a consideration.
Many alternative diets are produced by smaller companies that may not do nutrient analyses or feeding trials. It is more likely that an alternative diet would not have a nutritional adequacy statement, compared to a conventional diet.
For alternative diets that are homemade, unless a recipe has been formulated by a nutritionist, veterinarian, or board-certified veterinary nutritionist, for that specific pet, the homemade diet is likely deficient in several essential nutrients.
What are conventional diets?
Conventional diets are the typical dry kibble or canned foods that most people think of when they hear “cat food”. These diets are manufactured in a production plant and sold through various retailers such as pet stores, grocery stores, or big-box stores. They usually contain one or more animal protein sources (often chicken, beef, pork, or fish), a dense carbohydrate (often grains), and perhaps some fruits and vegetables. They also contain oil (to supply essential fatty acids) as well as vitamin and mineral supplements.
Most traditional, commercial pet foods are made from byproducts of human food production. A common myth is that byproducts are bad, but they can be very rich in nutrients and can enhance the quality of a pet food. There are strict regulations on what is allowed as a byproduct for animal consumption. Dead carcasses, roadkill, or anything contaminated with fecal matter are not allowed. Organ meat, however, is acceptable.
What are alternative diets?
Alternative diets target cats or owners who need or prefer certain qualities in cat food. Some examples of diets that fall into that alternative category include grain-free, plant-based, raw, freeze-dried or dehydrated raw, fresh food diets, and homemade diets. They may also include limited ingredients (a single protein and a single carbohydrate) to reduce the effects of food allergies. See below for a brief description of each of these diet types and important considerations for each.
Grain-free or gluten-free
Gluten is a protein found in certain grains, including barley, wheat, and rye, but there are grains that do not contain gluten. Gluten-free does not mean grain-free. All grain-free cat foods are gluten-free, but not all gluten-free cat foods are grain-free.
Some pet owners may reach for grain- or gluten-free in a misguided effort to reduce GI upset or skin irritation suspected to be related to a food allergy. Allergies to grain and gluten are very rare in cats. Another common misconception is that grains are used as fillers and have no nutritional value. This is incorrect and, in fact, grains can be excellent sources of important nutrients such as iron, calcium, and several B vitamins, like thiamine, riboflavin, and niacin.
Plant-based
Plant-based diets do not use any animal-based ingredients. While it is true that cats need nutrients, not ingredients, and they can get those nutrients from a variety of ingredient combinations, there is no strong research investigating the cat’s ability to digest and absorb nutrients from plant-based ingredients. Cats are obligate carnivores and have specific nutritional idiosyncrasies that make them quite different from dogs. They may not be able to thrive on a plant-based diet.
Raw, dehydrated raw, and freeze-dried raw
These are typically meat-based diets and may or may not include carbohydrate ingredients. Raw means the food has not been cooked; several forms of raw diets are available commercially in pet stores and other retail locations. The Canadian Veterinary Medical Association (CVMA) has a position statement that indicates the risks of feeding raw diets currently outweigh any purported benefits. Dehydrating and freeze drying are not considered methods that would result in a reduction in pathogen load and therefore are considered just as risky as raw meat diets.
Fresh diets
This is a newer alternative diet that has been growing in popularity and there are now a few companies making fresh food diets for cats. A fresh diet resembles a homemade diet but is prepared by a company and is purchased by the pet owner from a retail location. There is a large variety of ingredient options available and varying nutritional adequacy of these diets. An additional concern is whether a company manufacturing this type of diet is following any food safety guidelines to ensure the diets do not contain any pathogens or contaminants.
Homemade diets
This type of alternative diet involves the pet owner purchasing ingredients and personally making the food for their cat. Homemade diets allow for complete control over what is being fed to your cat and can be a great option if your cat has specific nutritional requirements. It can be risky to create a homemade diet on your own, without support from your veterinarian, an animal nutritionist, or a board-certified veterinary nutritionist. Research that investigated recipes available online for dogs and cats found that nearly all of them were deficient in one or more essential nutrient.
Limited-ingredient diets
These diets typically include only one animal protein and one dense carbohydrate ingredient and are targeted towards pets with suspected food allergies. If you are considering this type of diet for your cat, keep in mind that cat foods sold over the counter (non-veterinary diets) are likely to be at risk for cross contamination during manufacturing. Although only one protein source is listed on the label, it’s possible the food came in contact with other protein sources. A helpful way to think about this is to consider a human with a peanut allergy. Even if a food doesn’t contain peanuts, it could still cause a reaction if it was not manufactured at a peanut -free facility.
When would an alternative diet be a better choice?
There are some instances where an alternative diet might be a good choice for your cat.
- If your cat has suspected food allergies, then an alternative diet with limited ingredients could be an appropriate choice.
- Conventional pet foods use some ingredients and preservatives to keep the food fresh in the packaging and some cats may have intolerances to one or more of these ingredients. In these instances, a freshly prepared or homemade diet might be better tolerated.
- Pet owners may have specific preferences for the ingredients their pets eat for personal, religious, or other reasons. Feeding an alternative diet allows for more control and input over what ingredients are included.
- For cats that are very picky, a freshly prepared or homemade diet might be more palatable, although this may not be true for cats that have never eaten human foods.
- For pets that have multiple medical conditions in which nutrition can have a role, a homemade diet can be a great option that allows for a unique, individualized recipe to be prepared.
How else can I tell whether the diet I have chosen is right for my cat?
Aside from being complete and balanced, these additional factors can help you evaluate whether a diet is an appropriate choice for your cat.
- Is the food for the appropriate species and life stage (e.g., growth, adult maintenance)?
- Is your cat in a good body condition (not over- or underweight) and able to maintain a healthy weight?
- Does your cat have normal muscle condition (no muscle loss)?
- Are bowel movements formed and regular without blood or mucus?
- Is your cat’s skin and hair coat healthy and shiny?
- Does your cat have a good activity level?
- Does your cat eat the food when it is offered without leaving large amounts behind?
- Does your cat have any health conditions that would require modifications to the intake of specific key nutrients?
For now, no published research has found any benefit to feeding alternative diets compared to conventional diets for the general population of cats. There are case reports that document one cat (or several, if it is a case series) with specific medical conditions for which an alternative type of diet (usually homemade) has been prescribed because no appropriate conventional option existed – but these are specific to the pet in the case report.
If you think your pet would benefit from an alternative diet, speak to your veterinarian to learn more about what options would be the best fit for your individual cat.
