Feline Biology: The Case For Raw Feeding
- Everwell Pets
- Sep 3
- 7 min read
Cats are not tiny vegans, no matter how much you’d love to share your green smoothie with them. They are apex obligate carnivores. Yet, somewhere along the way, we decided to feed them dry, crunchy pellets full of corn and rice. The result? A dramatic shift in feline health, with skyrocketing cases of thyroid disease, kidney failure, and diabetes. Let’s take a closer look at how we got here, why it matters, and what you can do to help your cat thrive again.
Cats Are Obligate Carnivores
An obligate carnivore is an animal that must consume animal flesh to survive because it cannot obtain all the essential nutrients it needs from plant matter or other non-meat sources
Cats require nutrients like taurine, arachidonic acid, and preformed vitamin A, all of which are only found in animal tissue [1]. Unlike humans (or even dogs), cats cannot thrive on carbohydrates. Their digestive system lacks the enzymes to handle them efficiently, and excess carbs turn into sugar spikes and fat storage.
Here’s why: cats completely lack salivary amylase, the enzyme that in omnivores (including humans) starts breaking starches down in the mouth [2]. Their saliva is only for lubrication and killing bacteria—not digestion. Deeper in the digestive tract, they produce much lower levels of pancreatic amylase and disaccharidase enzymes (like maltase and sucrase) compared to omnivores, and these enzymes do increase even in response to being fed a high-carb diets [2,3].
It doesn’t stop there. Cats also lack the liver enzyme glucokinase, which in other species helps process glucose surges after a carbohydrate-heavy meal. Instead, they rely on hexokinase, which works, but far less efficiently [2].
Translation: cats are simply not equipped to handle sudden sugar spikes. This mismatch between diet and metabolism is a big reason why carbohydrate-heavy foods have been tied to obesity, diabetes, and even inflammatory bowel disease (IBD). In fact, studies suggest that cats with IBD often do better on low-carbohydrate, novel-protein diets, while high-carb foods can worsen post-meal inflammation [4,5].
The Rise of Kibble: Convenience Over Biology
Kibble was introduced in the mid-20th century as a convenient, shelf-stable solution for pet owners [6]. It was cheap to produce, easy to store, and marketed as “complete and balanced.” The catch? To make those crunchy nuggets, manufacturers had to load them with carbohydrates and fillers to hold their shape.
Cats may have adapted behaviorally to kibble—they’ll eat it and sometimes even beg for it—but physiologically, they’ve suffered. Their bodies never signed up for a high-carb, highly processed diet. The shift to kibble coincided with a sharp decline in feline health across the board [7]. Convenience for us has come at a cost for them.
Kibble Shifts Fuel Chronic Vomiting
A cat’s stomach is a high-performance meat-processing system—when it’s fed what it’s designed for. In a natural state, feline gastric acid maintains a very low pH around 1–2, triggered by protein-rich prey. This highly acidic environment is essential for breaking down meat efficiently, sterilizing ingested material, and digesting the fur cats inevitably swallow during grooming [8].
When cats are fed high-carbohydrate, processed diets, that acid response is blunted. Instead of dropping to the ideal 1–2 range, the stomach often lingers closer to pH 4–5, far too mild for proper digestion [9]. Without strong acidity, both food and hair sit longer in the stomach, slowing gastric emptying and making vomiting more likely. What should have been digested and passed through the intestines ends up being expelled instead.
This mismatch between diet and physiology is a major reason so many kibble-fed cats vomit regularly. It’s not “just hairballs”—it’s the stomach struggling in an environment it was never built for. Many owners find that once carbohydrates are removed and meat-based diets are introduced, the frequency of vomiting decreases dramatically [9,10].
Ultra Processed Foods = Achy Joints
In humans, the evidence is piling up: diets high in ultra-processed foods (UPFs) are bad news for our joints. Studies have linked UPF consumption to thinner knee cartilage, greater functional disability, and higher risk of osteoarthritis progression [11]. Even when total calories and exercise are controlled, UPFs are associated with fat infiltrating into muscles, weakening the very scaffolding that supports and protects joints [12]. On top of that, processed food drives chronic low-grade inflammation, fueling the breakdown of cartilage and accelerating arthritis [13].
Now let’s take that same logic and apply it to our cats. By the time they reach six years old, about 60% of cats already show radiographic evidence of osteoarthritis, often without obvious limping or pain [14,15]. That number soars to nearly 90% in senior cats [16]. While genetics and aging play roles, it’s fair to ask: how much is their processed, carbohydrate-heavy diet accelerating joint wear and inflammation? Just as processed food undermines human joints, kibble may be setting the stage for stiff, sore, less mobile cats, long before most owners recognize the signs.
The parallel is clear: neither our bodies nor theirs were built to thrive on factory-made food. Whole, nutrient-dense diets support joint integrity, muscle strength, and resilience, while processed ones quietly chip away at these foundations.
The Disease Explosion: Kibble’s Hidden Legacy
Hyperthyroidism and Hypothyroidism
Increased rates of thyroid disease have been linked to iodine imbalances and chemical compounds in processed foods [17]. Cats who once thrived on prey-based diets are now battling endocrine disorders at unprecedented rates.
Kidney Disease
Chronic kidney disease is one of the leading causes of death in cats today [18]. While genetics play a role, diet is a major factor. Cats are built to get moisture from their prey—mice are about 70–80% water. Kibble, on the other hand, hovers around 10%. That chronic dehydration forces the kidneys to work overtime, wearing them down year after year.
Diabetes
Carbohydrate-heavy diets wreak havoc on feline blood sugar. Cats were never meant to process large amounts of starch, and kibble can lead to constant insulin spikes, insulin resistance, and eventually full-blown diabetes [19].
Returning to Nature By Transitioning to Raw
A true species-appropriate diet mimics what cats would eat in the wild: muscle meat, organs, and bone in the right proportions [21]. This can be achieved through high-quality commercial raw diets or carefully balanced DIY meals. Variety is key—feeding only chicken breast isn’t enough. And while some worry about raw being unsafe, the reality is that, with proper sourcing and handling, raw diets are both safe and profoundly beneficial [22].
Here’s the truth: switching a cat to raw food can be a bit like negotiating with a stubborn toddler—it’s possible, but it might test your patience. Cats are naturally neophobic, meaning they’re suspicious of anything new on their plate [20]. Some will surprise you and dive right into raw meat (lucky you—don’t overthink it, just keep offering different proteins and brands). But for most, it takes persistence, creativity, and a little feline psychology.
The first step isn’t even about raw—it’s about meals instead of free-feeding. If you’re leaving kibble out all day, start by offering breakfast and dinner only. This simple change helps regulate insulin, improves digestion, and sets the stage for real dietary upgrades. Once your cat is eating on a schedule, replace one kibble meal with either canned food or raw. Don’t mix them together—kibble, canned, and raw digest at different rates and stomach pH levels, which can create more tummy upset than progress.
If your cat accepts canned food, celebrate—it’s already a huge step up in moisture and meat content compared to dry. If raw is accepted straight away, consider yourself blessed and keep building on it. But if your cat sniffs the raw and gives you that classic feline look of disdain, don’t give up after two tries. Transitioning to raw is often a marathon, not a sprint.
Get creative. Cats are natural hunters and mischief-makers, so sometimes placing raw food in unexpected places works—a favorite spot in my house is the bathroom sink. Roll raw into kibble-sized bites if that’s what they’re used to. These little tricks are usually temporary, just to spark curiosity. And always remember: cats prefer food at room temperature, not straight from the fridge.
The goal is steady progress, not perfection overnight. Every step that reduces kibble and increases fresh, species-appropriate food is a win for your cat’s long-term health.
The goal is to feed your cat like the predator they were born to be. Because deep down, your couch potato is still a mighty hunter—just ask the toy mouse under your fridge.
In Conclusion
Cats are carnivores, not carb-ivores. Kibble may have been convenient, but it’s left a legacy of chronic disease and shortened lifespans. By returning to a raw, species-appropriate diet you give your cat the chance to reclaim their health, vitality, and longevity.
So next time you’re filling their bowl, ask yourself: does this look like something a wildcat would eat? If not, it may be time to make the switch. Your cat deserves to eat like the predator they were born to be.
Curious about how to make the raw transition safely? Book a consult with Dr. Andi for personalized guidance. Or join the Everwell Pets Unleashed Membership to access exclusive resources, raw-feeding support, and a community of like-minded pet parents.
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Citations
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