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Home > Cats > Why Do Cats Have Belly Pouches (Primordial Pouch)? 3 Vet-Approved Theories and What They’re Used For

Why Do Cats Have Belly Pouches (Primordial Pouch)? 3 Vet-Approved Theories and What They’re Used For

cat with belly pouch outdoors

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Dr. Paola Cuevas

Veterinarian, MVZ

The information is current and up-to-date in accordance with the latest veterinarian research.

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If your cat looks like their belly is swinging around beneath them, it’s not because they’re overweight; rather, they have a primordial pouch. It’s comprised of skin, fur, and fat and is positioned along the underside of a cat’s belly for protection. It’s normal for cats to have these pouches, but they can vary greatly in size. So, while one cat’s pouch might be barely noticeable, another’s might swing along the ground.

There are three primary theories as to why cats have primordial pouches. Let’s look at each one.


The 3 Theories Why Cats Have Primordial Pouches

Theory 1: The Primordial Pouch Is for Protection

The first theory regarding the presence of the primordial pouch in felines is that its presence provides protection. It adds an extra layer of protection for internal organs from claws and teeth.

Theory 2: It Enables the Cat to Move Faster

The second theory surrounding the presence of the primordial pouch is that it enables cats to move faster. The pouch stretches out when cats run, giving them added flexibility and the ability to reach farther with each step, a great quality for cats trying to evade predators or catch prey.

Theory 3: It Serves as an Energy Reserve

The third theory is that the primordial pouch provides extra space for cats to store energy in the form of fat. While we mostly think about domestic cats, wild cats don’t get two bowls of kibble each day. Sometimes they go for days without a meal, so they eat when they can and store fat in their pouch to provide them with sustenance for the days to come.

cat with belly pouch outside in the fields
Image Credit: Santa3, Pixabay


Facts About the Primordial Pouch

Primordial pouches aren’t unique to domestic cats; they are also found on many species of wild cats, including tigers and lions. The pouch develops around 6 months of age and is present in both males and females.

Whether a domestic cat has a large primordial pouch is based on their genetics. This trait has been passed down from wild cats through generations, so while it doesn’t have much of a purpose in domestic felines, they still carry the trait. Primordial pouches are more prevalent in some purebred cat breeds, as their genes have less variety, making it less likely that physical characteristics were lost through breeding.

ragdoll cat outdoors
Image By: Atmosphere1, Shutterstock

Distinguishing Between a Primordial Pouch and Extra Weight

It is important to distinguish whether your cat’s sagging belly is a primordial pouch or if they are overweight. Obesity is a common problem in house cats and can lead to heart problems, hypertension, joint problems, and diabetes.

Looking at your cat’s shape is one way to distinguish between the two. Cats that are obese have an overall rounded body shape than cats at a healthy weight. You should be able to see an indentation at your cat’s hips. The belly of an overweight cat will start at the top of their underside and extend down, but primordial pouches start underneath and are located toward the back legs.

You can also check whether you can feel your cat’s ribs by pressing on their body. If you have to press really hard to feel their ribs, your cat is probably overweight. Also, primordial pouches swing when a cat runs or walks, whereas overweight bellies do not.

Knowing the difference between a natural pouch and excess fat can be confusing, especially when you simply look at pictures of fat cats online. It can be challenging to know what “normal” looks like. 

Here are the most common signs that your cat needs to shed a few pounds:
  • Rib and hip bones being difficult to feel
  • Difficulty jumping or climbing
  • Less visible waistline
  • Poor grooming habits
  • Lethargy
  • Cat’s collar keeps tightening



Primordial pouches are normal physical features in cats. Some cats have bigger ones than others, and it seems that the pouch may have provided some sort of protective measure for wild cats. While there are different theories on the function, it has been passed down through generations from wild feline ancestors. Distinguishing the primordial pouch from obesity is important to keep your cat healthy. If you feel that your cat is overweight, talk to your veterinarian about how to encourage weight loss for your cat’s longevity and overall health.

Featured Image Credit: Zanna Pesnina, Shutterstock

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