If you’ve ever been licked by a cat, you know the sensation is nothing like a dog’s slobbery kiss. A cat’s tongue feels like wet sandpaper — rough, textured, and surprisingly abrasive. That distinctive texture isn’t accidental. It’s the result of millions of years of evolution, and the cat tongue is one of the most sophisticated grooming tools in the animal kingdom.
Why Is a Cat’s Tongue Rough?
The roughness comes from tiny, backward-facing spines called papillae that cover the surface of the tongue. These papillae are made of keratin — the same protein that forms human fingernails and cat claws. Each papilla is hollow and scoop-shaped, roughly 2mm long, and pointed towards the throat.
Research published in the Proceedings of the National Academy of Sciences (2018) used CT scanning and high-speed video to reveal that these spines aren’t just hooks — they’re tiny scoops that wick saliva from the mouth and deposit it deep into the fur during grooming. Each lick distributes about 50% of the available saliva on the tongue surface directly onto the skin.
What Does a Cat Use Its Tongue For?
Grooming
Cats spend between 30–50% of their waking hours grooming. The papillae act as a built-in comb, detangling fur, removing loose hair, distributing natural skin oils, and eliminating parasites. This is why cats rarely need baths — their tongue does the job. The saliva also has mild antibacterial properties, which helps keep minor wounds clean.
The downside of this efficient grooming is hairballs. The backward-facing papillae make it almost impossible for a cat to spit out loose fur — it gets swallowed instead. Long-haired breeds like Maine Coons and Persians are particularly prone to hairball issues. Regular brushing reduces the amount of loose fur your cat ingests.
Eating
The papillae help cats scrape meat from bones — a holdover from their wild ancestor’s diet of small prey. Domestic cats still use this technique with wet food, pulling it off the plate and towards the throat rather than using teeth to chew in the way dogs or humans do.
Cats also have far fewer taste buds than humans (about 470 compared to our 9,000). They can’t taste sweetness at all — they lack the gene for the sweet receptor. This is why cats show zero interest in sugar, fruit, or most desserts. For more on feline diet, read our guide to what cats like to eat.
Drinking
Cats don’t scoop water like dogs. High-speed cameras reveal that a cat touches the tip of its tongue to the water surface and immediately pulls it back, creating a column of liquid that the cat catches by closing its mouth at exactly the right moment — roughly four times per second. It’s a feat of timing and physics that researchers at MIT described as “elegantly exploiting the balance between gravity and inertia.”
Temperature Regulation
When a cat grooms, the saliva deposited on the fur evaporates and cools the skin — similar to how human sweat works. Since cats don’t sweat through their skin (only through their paw pads), grooming is their primary cooling mechanism. In South African summers, you may notice your cat grooming more frequently — this is thermal regulation, not anxiety.
What a Cat’s Tongue Tells You About Their Health
- Pale tongue: May indicate anaemia or poor circulation. This warrants a vet visit.
- Yellow tongue: Could suggest liver issues (jaundice).
- Bright red or inflamed tongue: Possible infection, stomatitis, or an allergic reaction.
- Tongue sticking out constantly: Usually harmless (the “blep”) but if persistent, could indicate dental pain, neurological issues, or respiratory problems.
- Excessive grooming/licking: Often a sign of stress, pain, or skin conditions rather than cleanliness. If your cat is overgrooming to the point of creating bald patches, consult your vet.
Why Do Cats Lick Their Owners?
When your cat licks you, they’re doing one or more of the following:
- Social bonding: Cats groom each other (allogrooming) to reinforce social bonds. Licking you is the same behaviour — you’re being accepted as part of the group.
- Taste: Your skin has salt, oils, and residual food flavours that interest a cat.
- Scent marking: Saliva carries scent. By licking you, your cat is depositing their scent and claiming you as “theirs.”
- Comfort seeking: Kittens lick their mother during nursing. Adult cats sometimes revert to this behaviour for comfort, particularly if they were weaned early.
The cat tongue is a remarkable piece of biological engineering — a grooming tool, eating utensil, thermometer, and social bonding mechanism all in one. Next time your cat gives you that sandpaper kiss, appreciate the millions of years of evolution behind it.
Want to understand more about your cat’s behaviour? Explore our guides to why cats knead, why cats purr, and why cats meow.
