Cats: Understanding Species-Appropriate Feeding for Obligate Carnivores
Cats are notoriously selective eaters, and transitioning them to a raw, species-appropriate diet can present challenges for many guardians. This difficulty is compounded by the highly palatable nature of commercial dry foods, often referred to colloquially as “kitty crack” due to their addictive qualities. Despite these hurdles, understanding the biological and physiological needs of cats—particularly their status as obligate carnivores—provides essential context for why raw feeding is an optimal approach to feline health.
This article explores the scientific rationale behind raw feeding for cats, contrasts feline and canine carnivory, explains the critical role of dietary moisture, and discusses the health implications of feeding carbohydrate-laden, ultra-processed foods.
Obligate vs Facultative Carnivores
Household cats, of all breeds, are obligate carnivores by nature. Meaning, their physiology has evolved to depend on nutrients found exclusively in animal products. Unlike facultative carnivores like dogs, which perform best on a highly animal based diet, can obtain sufficient nutrients to survive (not thrive) from plant based foods, cats require specific nutrients that cannot be sufficiently obtained from plant matter or carbohydrate-based diets.
Key nutritional characteristics of obligate carnivores include:
High animal based protein and fat requirements for maintenance of muscle mass, energy, immune function, and enzymatic activity.
Inability to synthesise essential nutrients, such as taurine, preformed vitamin A (retinol), and arachidonic acid, which must be sourced directly from animal-based foods.
Dependence on dietary arginine for proper nitrogen metabolism—deficiency can result in rapid onset hyperammonemia.
Lack of salivary amylase and minimal pancreatic amylase secretion, reflecting an evolutionary disinterest in carbohydrate digestion.
In contrast, dogs as facultative carnivores can adapt more flexibly to mixed diets, though a meat-based foundation remains optimal for their health. Cats, however, must consume animal proteins to meet their basic physiological needs. In highly processed dry and canned foods, essential nutrients for cats are often added as a synthetic supplement.
Bioavailability of Animal-Based Nutrients
A critical and often overlooked aspect of feline nutrition is the bioavailability of nutrients—the proportion of a nutrient that is digested, absorbed, and utilised by the body. In obligate carnivores, nutrients derived from animal tissue are significantly more bioavailable than those from plant-based ingredients.
Cats are evolutionarily adapted to digest and assimilate nutrients in the specific chemical forms found in animal prey. For example:
Preformed vitamin A (retinol) from liver is readily absorbed, whereas beta-carotene from plants is poorly converted and largely ineffective in cats.
Taurine, an essential amino acid for cats, is found exclusively in animal protein and is either absent or functionally unavailable in plants.
Heme iron from meat is better absorbed than non-heme iron from plant sources.
Zinc, B vitamins, and fatty acids (like EPA and DHA) are all more efficiently utilised when sourced from animal tissue.
Relying on plant-based nutrients in feline diets can lead to marginal deficiencies over time, even when crude nutrient levels appear adequate on a label. This further underscores the importance of feeding a diet based on whole animal ingredients.
The Importance of Dietary Moisture
One of the most critical differences between raw and dry feeding is moisture content. Cats evolved as desert-dwelling predators; they are physiologically adapted to obtain the majority of their water from prey. Raw meat, organs, and connective tissues contain approximately 65–75% water, closely mimicking the natural composition of whole prey.
Dry foods, by contrast, typically contain less than 10% moisture. Even with access to fresh water, many cats on a dry diet do not compensate by drinking adequately. Chronic, low-grade dehydration is common and contributes to urinary tract disease and kidney dysfunction. Feeding raw or other wet diets from early life may play a preventive role in the development of chronic kidney disease, one of the most common causes of mortality in domestic cats.
Carbohydrates
While cats can metabolise small amounts of carbohydrate, their natural diet contains minimal starch or sugar. Most commercial dry foods are composed of 30–50% carbohydrate (often from corn, wheat, rice, or legumes), far exceeding what is considered species appropriate.
High dietary carbohydrate intake is associated with the following health conditions in cats:
Diabetes mellitus, particularly type 2-like insulin resistance, due to chronic hyperglycaemia and pancreatic stress
Obesity, driven by the overconsumption of high-glycaemic, low-satiety diets
Inflammatory bowel disease (IBD), potentially exacerbated by non-ultra processed proteins, carbohydrates and additives
Arthritis and other inflammatory disorders, linked to systemic inflammation driven by hyperinsulinaemia and advanced glycation end products (AGEs)
There is even speculation that the increased use of ultra processed diets (along with an increase in flea and tick medications, vaccinations and other medical treatments) is directly correlated to the increased risk of cancer. Reducing dietary carbohydrate and increasing whole food, raw, species-appropriate animal protein and fat can significantly improve metabolic health and reduce disease risk in feline populations.
Challenges of Transitioning
Many cats resist dietary change, especially moving from ultra processed dry or canned food to a natural raw diet. This fussiness is not a reflection of what is best for the animal, but rather a conditioned preference formed during critical feeding windows. The smell, texture, and high flavouring agents in dry food can override natural preferences.
Strategies for transition include:
Slowly integrating small amounts of raw or wet food into the current diet, gradually increasing the proportion over days to weeks
Warming raw food slightly or lightly cooking to enhance aroma and mimic prey temperature
Offering food at routine meal times and removing uneaten food after 20–30 minutes to encourage hunger-driven interest
Using transition tools, such as freeze-dried raw toppers or bone broth, to bridge textures and flavours
Avoiding coercion—cats must be permitted to transition at their own pace, especially those with prior gastrointestinal sensitivities
Some cats transition readily; others may require several months of gentle encouragement. Always ensure dietary changes are gradual and supported by a complete and balanced raw diet formulated for feline needs.
Responsible Feeding
When feeding a raw diet to cats, formulation must account for their specific micronutrient needs. Taurine, calcium-phosphorus ratios, and fat-soluble vitamins (A, D, E, K) must be balanced appropriately, whether the diet is homemade or commercial. Organ meats such as liver and heart are essential components, and variety in muscle meat may helps prevent nutrient gaps however seeking professional nutritional guidance or following reliable recipe and education sources are paramount if continuing with a home made raw diet long term.
Food safety is also critical. Proper hygiene, sourcing, and storage are required to minimise microbial risk. Many cats tolerate raw food well, but immunocompromised individuals may benefit from lightly cooked, calcium supplemented formulations during initial transition phases.
Conclusion
Feeding cats a species-appropriate raw diet honours their evolutionary biology as obligate carnivores. It provides moisture, bioavailable nutrients, and a macronutrient profile aligned with feline physiology. While transitioning cats from dry food can be challenging due to behavioural imprinting and sensory preferences, the long-term health benefits—including improved renal function, metabolic stability, and reduced inflammatory disease—make it a worthwhile pursuit.
As with any nutritional change, raw feeding should be approached with knowledge, care, and a commitment to meeting the animal’s full nutrient requirements. While this information is intended for educational purposes and does not constitute veterinary advice, it reflects current nutritional science supporting biologically appropriate feeding strategies for companion cats.