If you think your feline is fat, it may actually just be a primordial pouch showing. Wait, what's that? We're guessing this is the first time you're hearing that term, and we admit it sounds a bit odd for sure. This loose flap of skin along a cat's belly is often mistaken for a growing gut, but it shouldn't alarm cat owners at all.
A cat's primordial pouch is located along the length of its stomach, but you'll notice it most closer to the rear. Often, the primordial pouch will sway when a cat walks or runs. Of course, any time a pet owner notices what looks like their cat's stomach jiggling, it's natural to assume this is related to weight gain. But actually, a primordial pouch can appear on all cats, regardless of whether they're slim or a bit chunky.
Experts aren't quite sure why cats have primordial pouches, but they have a few theories. First, the pouch serves as protection in a fight, as it shields vital organs from an attacking cat's sharp claws. Even if a cat's primordial pouch is injured, the important internal organs may still be intact.
A second biological explanation for the primordial pouch is that it allows cats to stretch out more when they run. If you've ever see a video of a cat running in slow motion, you immediately notice how far out they reach with their front paws. In theory, the primordial pouch makes them more flexible.
It's possible that the primordial pouch exists as extra storage during a feast. Wild cats don't know where they're going to find their next meal (unlike our spoiled domestic kitties), so they often gorge themselves so they have extra fat stores. Dovetailing off that explanation, the primordial pouch could also have functioned as a fat reserve in lean times.
To tell whether a cat is overweight or if it's simply a primordial pouch, pay attention to your cat's motions. If the bulge jiggles from side to side, it's probably a primordial pouch and not a case of an overfed cat.