Can Dogs Smell Human Pheromones? Here’s What Science Says (Vet-Reviewed)

Have you ever been entertaining guests only to have your dog suddenly plonk their nose right in places you wish they wouldn’t? As embarrassing as this is for you and maybe your guests, your dog is just learning a little more about you.

This might lead you to wonder if dogs can smell our pheromones or not? Well, dogs have incredible noses and can indeed smell human pheromones and other chemical compounds our bodies excrete!

If you’re interested in learning more about the dog’s nose and what they discover about us and the world around them, keep reading!

How the Dog’s Nose Works

There’s no question that dogs have an incredible sense of smell, and it’s all in the olfactory receptors. Dogs have up to 300 million olfactory receptors, and to put that into perspective, humans have only 6 million.¹

And to put it into even more perspective, dogs could smell one drop of substance in 20 Olympic-sized swimming pools!²

And their sense of smell doesn’t activate only their noses but also a part of the dog’s brain. This section of the brain is about 40 times larger than our part of the brain that analyzes scents. But how exactly does the dog’s nose work?

Dogs Smell Continuously

If you really look at your dog’s nose, you should notice that, like us, they have two nostrils, but unlike us, they also have slits on the side of each nostril.

So, when humans inhale a scent through our noses, we are both inhaling and breathing through the same airway. But when dogs inhale, tissue inside the nose separates the air for breathing and the scent.

Now, when humans exhale, the air is pushed through the same way it entered, which will additionally prevent us from smelling anything. When dogs exhale, the air exits through those slits, allowing it to swirl around and for new odors to enter the nostrils again.

Therefore, the dog can more or less continuously smell something. They also have great control of those nostrils as they can actually wriggle or move each one separately. So each nostril can pick up a scent that the dog can locate based on which nostril the scent is closest to.

What About Smelling Pheromones?

Those talented noses can determine all kinds of things that give them information. They can tell through sniffing if another dog is male or female or even how they are feeling – if they are aggressive, happy, or even sick, based on the pheromones and other molecules they emit, alongside their body language and visual cues.

And this goes for us as well as dogs, detecting how we’re feeling and if we are sick based on the different smells produced by our bodies in various physical and emotional situations or associated with illness, which dogs can pick up in our breath or sweat. And they will go out of their way to chew on your used shoes or even underwear because of the pheromones and other scents that are on them. This is how they get to know you and tend to prefer our things to remain unwashed because the scents are stronger and more appealing to them.

However, human pheromones remain a bit of a mystery as scientists have not yet reached an exact consensus on their definition and importance in people, but for the purpose of this article, we decided to use the word pheromone. Our dogs are able to pick up on many scents emitted from our bodies in various situations and pheromones are just one of them.

Can Dogs Smell Our Fear?

When you hear about dogs sensing our fear, that is actually true in a way. When we are scared or very stressed, we secrete the hormone adrenaline, which dogs can actually detect.

They can also smell the body chemicals released when our heart is racing, in addition to the increased blood flow. So, there’s not much we can do about hiding how we’re feeling from any dog.

What Gives Dogs the Ability to Smell Pheromones?

Beyond the fact that dogs can smell 10,000 to 100,000 times better than us and that they can sniff and smell odors continuously, they also have something called the vomeronasal organ.

Also known as Jacobson’s organ, it is situated inside the nasal cavity and the roof of the mouth. It’s this organ that gives dogs the ability to detect pheromones. Its main function is for the detection of pheromones, but it is additionally for odors that are usually undetectable.

It is used to identify threats from another animal but primarily its role is for breeding purposes. For example, males can detect when a female is in heat through her urine.

Many dogs will also engage in the flehmen response when they smell something of great interest (like urine) in which they might chatter their teeth or look like they’re licking or sniffing the air.

This opens up the Jacobson’s organ, allowing the dog to gain much more information from the scent of pheromones.

What Can Dogs Detect from Human Pheromones?

Beyond detecting our emotions, like fear or stress, dogs may be capable of telling if we are male or female but this does require further scientific research.

Dogs may also be able to detect certain illnesses, and studies have shown they can alert to different kinds of cancer by picking up on various volatile organic compounds produced in the body. They can smell it on our skin, urine, sweat, and breath.

But this can all help explain why our dogs enjoy sticking their noses into awkward places because they gain a lot of information this way.

While humans are also capable of detecting pheromones, we just are nowhere near as good at it as dogs.

Can Dogs Remember Scents?

They absolutely can! This is why an owner can be reunited with their dog after years and the dog still remembers them. This is in combination with voice and facial recognition but scent plays a significant role.

In fact, a dog will remember their owner for the rest of their life, even when separated for years!

And you’ve likely heard the stories about dogs lost and far away from home but still managing to find home.

Dog Breeds With the Best Sense of Smell

All dogs really do have an excellent sense of smell, but some may be better than others:

Although we still do not have all the answers to why some breeds may have better olfaction than others, it seems there is a genetic reason for this in the expression of genes responsible for the sense of smell

Summary

Dogs have such excellent noses that many breeds have jobs that rely on their sense of smell. Imagine being able to smell a bomb or counterfeit money!

And while pheromones have no discernible smell, dogs gain such an enormous amount of information when they sniff another dog’s bum or their private parts. In fact, having a wet nose additionally adds to their sniffing prowess.

So many factors go into their sense of smell, so let your dog sniff to their heart’s content while you’re out and about with them. They are learning some pretty important information!

Featured Image Credit to Irina Kozorog, Shutterstock