Obesity is a common problem in domestic cats, but your cat’s hanging belly doesn’t necessarily mean that she is overweight.  The low hanging flap of extra fur, skin, and fat that you may notice on some cats’ undersides is called a primordial pouch.

The primordial pouch is common to all cats—male and female–including big cats like lions and tigers.  It is not related to obesity, spay/neuter, or whether a cat had kittens.  It just may be larger and more noticeable in some cats than others.  Larger pouches often swing back and forth as a cat walks.

Why do cats have a primordial pouch?  According to José Arce, president-elect of the American Veterinary Medical Association, there are a few possible reasons.  As he explains to the website Live Science, cats may have this extra fur, skin, and fat under their stomachs because:

• It serves as a layer of protection for the internal organs during fights.
• It helps cats move faster by giving them greater flexibility and range of motion when they run.
• It may help them store extra food after they eat a large meal.

A large pouch is not a good indicator of obesity in cats.  Dr. Arce says the overall body shape of an overweight cat is round.  Here’s a helpful chart that shows how you can determine your cat’s body condition:

Overweight cats are barrel shaped when seen from above, but the pouch is under the body towards the rear legs.

Your cat’s belly “pooch” is totally normal and harmless.  In fact, according to the Cat World website, the primordial pouch is even written into the breed standards for some cats like the Bengal, Egyptian Mau, and Pixie-Bob.