Skip to main content

Whether it’s getting every last morsel of food from their bowl, panting after a game of fetch, or showering you with affection, a dog’s tongue plays an important role in how they interact with their environment.

Here are some interesting facts that you probably don’t know about dog tongues.

Dogs pant to cool down instead of sweating.

Dogs don’t sweat in the same way as humans. They only have sweat glands on their paw pads and noses, which are called merocrine glands. Dogs also have apocrine glands all over their bodies, which is one way that humans sweat, but in dogs, these glands are primarily used to secrete scent pheromones, not sweat.

Instead of sweating, dogs rely on panting to keep cool. When dogs pant, air moves rapidly over their tongue and through their mouth and lungs, allowing moisture to evaporate and cool them down. This process is called thermoregulation and is incredibly important when a dog gets hot.

If you notice your pup panting excessively on a warm or hot day, get them into a cooler location and give them plenty of water to avoid possible heatstroke.

Dogs rely on smell over taste to decide if they want to eat something.

While dogs have more taste buds than cats, they have far fewer than humans. They only have around 1,700 taste buds, which is about one-sixth of what humans have (approximately 10,000!).

Like us, dogs can taste bitter, salty, sweet, and sour, but because they don’t have as many taste buds, they use their sense of smell far more than their sense of taste when deciding what to lick or eat. This is likely why dogs enjoy licking areas of our bodies that tend to have strong tastes and smells: our faces, ears, feet, and hands.

A dog’s tongue is usually warm.

If your dog’s tongue feels extra warm when they lick you, it’s likely because the normal body temperature for dogs is 101.0 to 102.5°F (38.3 to 39.2°C).

If your dog is running a fever, their tongue may feel even warmer, but don’t count on this as an accurate assessment of their body temperature. Taking a dog’s temperature by mouth is unreliable and, depending on the dog, not always easy or safe. The most accurate way to determine a dog’s body temperature is with a rectal thermometer.

If your dog has been panting in a cool room (or eating ice cubes or snow), their tongue may feel cool due to the evaporation of saliva from the surface of their tongue. However, it should quickly return to a warm temperature when they stop panting.

Not all dogs have a pink tongue.

When most of us think of a happy, panting dog, we imagine a bright pink tongue lolling out of the side of their mouth. A pink, moist-to-slobbery tongue is normal and healthy for most dogs, but two dog breeds of Chinese origin, Chow Chows and Shar-Peis, have blue or blue-black tongues. Mixes of those breeds may also have blue-black tongues or blue-black spots of coloration on their tongues.

If your dog’s tongue is normally pink, a sudden color change may indicate a medical emergency.

  • A dark red, purple, or blue-tinged tongue could be a sign of heatstroke, toxin exposure, heart/lung disease, or electrical shock.

  • A pale pink-to-white tongue could be a sign of severe anemia due to immune mediated disease, or internal bleeding.

If you notice these changes in your dog’s tongue, call your veterinarian right away.

Licking things has a calming effect on dogs.

Studies have shown that licking releases endorphins in a dog’s brain. Endorphins are neurotransmitters that make dogs feel calmer and more relaxed. However, licking may sometimes become a problem. If your dog licks you or themself excessively, especially in times of stress, talk to your veterinarian about possible anxiety issues in your pooch.

Dogs’ mouths are not cleaner than ours.

Contrary to popular belief, a dog’s mouth is definitely not cleaner than a human’s. Researchers have found that both dogs and humans have over 600 species of bacteria in their mouths.

However, while we both have mouths full of bacteria that are normal flora for our species, there are bacteria in your dog’s mouth that don't exist in yours and vice versa. Most of the bacteria in your dog’s mouth cannot cause you to get sick (you won’t catch the common cold from “kissing” your dog), but there are some exceptions, so stay safe and let your pooch give you a kiss on the cheek instead!

A dog’s saliva won’t exactly “heal” your wounds.

Another myth says that dog saliva can help heal wounds. In fact, some ancient Greek and Egyptian cultures also believed that dog saliva has healing powers. While licking can remove debris from a wound, therefore decreasing the chance of infection, too much licking can damage the skin and potentially lead to bigger problems, like hot spots.

But the ancients weren’t entirely wrong—there are proteins in saliva (human and canine) called histatins that inhibit infection. But dog saliva also contains bacteria that are normal flora in canine mouths but can cause dangerous infections in human wounds.

So, rather than letting your dog tend to your wounds, stick to more traditional care, such as washing with soap and water and talking to your physician about any possible infection.

You could be allergic to a dog’s saliva instead of their dander.

It’s hard to imagine living without the companionship of dogs, but 5-10% of the population can’t due to allergies. While it is often assumed that people with allergies to dogs react only to their skin dander, there is a portion of the population that is actually allergic to canine saliva.

If you or a friend seem to have an allergy to dogs, it may be worth talking to your dermatologist about whether that allergy is caused by a dog’s dander or saliva. You may be able to adopt a pup as long as you avoid their tongue!

Dogs don’t need rough tongues like cats do.

If you’ve ever been licked by a cat, you know that their sandpapery tongues feel much different than a smooth-tongued lick from a dog. But did you know that the difference in canine and feline tongues is likely due to their ancestors?

Cats have firm, rear-facing barbs on their tongues, called filiform papillae. These barbs act like a comb for the fur when cats groom themselves. Most wildcats hunt alone, but many smaller species of wildcats, including our domesticated feline friends, are small enough that they can also become prey for larger animals. This makes it important for them to keep themselves meticulously groomed, minimizing their odor for predators.

On the other hand, wild dogs (or domesticated dogs that live as strays) hunt in packs and nearly always play the role of predator in the food chain. This makes grooming and scent reduction far less important, so a smooth tongue meets their needs.

Some dogs’ tongues are too long for their mouths.

Macroglossia is the medical term for an abnormally large tongue and is a rare condition. True macroglossia is usually seen at birth when a puppy’s tongue is too large to allow them to latch onto a nipple and nurse normally.

However, some breeds of dogs (often short-faced breeds such as Boxers, Pugs, and English Bulldogs) can have tongues that are too long for their mouths, so part of their tongue always hangs out of their mouth.

These dogs may have difficulty eating and usually make a gigantic mess at the water bowl. They may also accidentally bite their tongues when playing with toys or snapping at a treat. Extra-long tongues don’t usually cause any medical issues, but if your dog has one, keep a close eye on it for accidental trauma or injury.

A dog’s tongue helps them communicate and interact with their world.

Dogs learn very early in life that their tongues are useful tools in communicating and interacting with the world around them. Mother dogs lick their pups to clean and stimulate them as soon as they are born. For the first few weeks of their lives, puppies are also licked by mother dogs to prompt them to urinate and defecate.

With wild dogs, puppies lick their elders to communicate submissiveness, but also to induce the regurgitation of food that the older pack members ingested while hunting. Pups will lick one another to show affection and also to comfort themselves and their littermates.

Dogs use their tongues and lick for number of other reasons: to better smell things they are interested in, to communicate anxiety, or to combat an upset stomach, for example.

They use their tongues in a similar way to how you use your hands—to explore the world around them! That may even include licking everything, like people, the floor, or even the air. Occasional, short-lived episodes of air-licking are not a cause for alarm, but you should watch for increases in the time spent and/or frequency of licking.

Your dog can’t help spilling their water when they drink.

If you’ve been lucky enough to live with both dogs and cats, you may have noticed that while cats rarely spill a drop of water while they’re drinking, many dogs splatter the floor with water when quenching their thirst. Why are dogs so messy and cats so neat?

The answer is in how dogs curl their tongues when they drink. Both cats and dogs dip their tongues into water and quickly retract it back, creating a column of water that they bite and then swallow. When they do this, cats move their tongues quickly (up to four laps per second), but dogs curl the tip of their tongue backward to spoon the water up into their mouths. The bigger the tongue, the bigger the spoon, and the bigger the mess!

Featured Image: iStock.com/debibishop

Help us make PetMD better

Was this article helpful?