Why Do Dogs Lick You? - PetMD

Why Do Dogs Lick People?

Licking is a natural instinct in dogs. Studies have shown that licking releases endorphins in a dog’s brain. Endorphins are neurotransmitters that make dogs (and us!) feel calmer and more relaxed. This then leads to a release of dopamine, another neurotransmitter associated with pleasure and motivation.

There are many things that dogs lick—some more repulsive than others. So, what does it mean when a dog licks you? There isn’t one straight answer. Dogs lick people for a variety of reasons, including affection, communication, grooming, exploration, attention, and taste.

Dogs Learn to Lick as Puppies

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 prompted to urinate and defecate by mom’s licking. So, dogs learn very early that tongues are useful tools in communicating and interacting with the world around them.

Puppies lick to appease older dogs, including their mom, and clear the way for safe social interactions. Pups will lick one another to show affection, and to comfort themselves and sometimes their littermates.

Dogs Lick People to Enhance Smell

Licking also enhances your dog’s sense of smell. Like humans, dogs can taste bitter, salty, sweet, and sour. But due to their small number of taste buds, they actually 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 hands, faces, ears, and feet.

To understand why dogs really enjoy licking certain areas of our bodies, let’s take a quick look at the anatomy of human sweat. We have two types of sweat glands: eccrine and apocrine.

• Eccrine glands secrete a thin, odorless, clear fluid made of salt, protein, etc., and are found in large numbers on the soles of the feet, the palms, the forehead, the cheeks, and in the armpits.

• Apocrine glands secrete a thicker fluid that reacts with the bacteria on your skin to create body odor and are found in the armpits and groin, but also in the ear canals, eyelids, and nostrils.

With all of this fun physiology, how could dogs resist licking parts of us that contain so much scent and taste?