What emotions Can dogs smell?

Why Dogs Care About Human Emotions

Our symbiotic relationship with dogs began 15,000 years ago when we offered them warmth, shelter, and food in exchange for protection and companionship.

That bond continues to grow and strengthen to this day. For example, canine pack members do not routinely look into each other’s eyes during bonding. In fact, this behavior is typically seen as a challenge or threat among dogs.

However, humans do engage in prolonged eye contact, especially with those we love. Domestic dogs have not only learned to look us in the eye, they’ve also “hijacked” the famous oxytocin gaze-positive loop most commonly observed between new mothers and their babies.

As our two species continue to evolve side-by-side, our smart, resourceful dogs persistently adapt to our way of life. They are so good at sensing our innermost feelings, it sometimes seems like they can read our minds!

Dogs Sense Our Emotions By:

1. Reading Our Body Language

Author and professor emeritus, Albert Mehrabian discovered that 93% of human communication is non-verbal. Both humans and dogs communicate through vocalization, but we also tend to trust what we see above what we hear.

When greeting a new pooch at the park, dogs avoid stiff, aggressive-looking pups in favor of happy, relaxed playmates. They do the same when it comes to sensing our emotions. A quick glance at our posture, gait, and mannerisms tells them everything they need to know about our current mood.

Dogs are so good at reading our body language they beat out wolves, chimps and three-year-old children in social cognition experiments. E ven nine-week-old puppies that have never lived as family pets scored better, suggesting this skill is evolutionary.

2. Studying Our Facial Expressions

Humans and primates have a social trait known as “emotional contagion.” It’s why we yawn when a friend yawns, and why we tend to return the smile of a passing stranger. Matching the emotions and physical expressions of our fellow humans demonstrates our high capacity for empathy.

Dogs also perform a similar kind of social mimicry with each other. Italian researcher Elisabetta Palagi and her team studied dogs interacting at the park and found that not only do they match each other’s body postures, they also mimic facial expressions, especially with dogs they’re already familiar with.

The authors believe emotional contagion also exists between dogs and humans. When our eyes meet theirs, they raise their eyebrows to show they’re engaged in the interaction. When a dog parent yawns, their dog often does the same.

3. Sensing The Emotion In Our Voice

Dogs can detect high frequencies and sounds more than four times farther away than humans can. Their powerful ears come in quite handy when dogs sense our emotions.

Studies show they respond similarly to humans when exposed to sounds of babies in distress. They become visually upset and release the stress hormone cortisol, suggesting they understand that crying is a negative human sound.

A 2014 study found that dogs can also detect variations in tone and mood in the voices of fellow dogs and humans. Just like us, they understand emotional voice cues which is another strong indicator they are capable of empathy.

4. Sniffing Out Chemical Changes In Our Bodies

Our dogs’ noses are 10,000 to 100,000 times more sensitive than our own with 300 million olfactory receptors compared to our measly 6 million. Scientists have likened their sniffing ability to “catching a whiff of one rotten apple amid two million barrels.”

Researchers at the University of Naples conducted a study to see if dogs could smell the difference between human body odors produced during happiness and fear.

Volunteer “odor donors” were shown a video to induce either fear or happiness, and their sweat was collected on pads. The canine test subjects were then exposed to samples of “happy sweat” and “fearful sweat.”

In the presence of the fearful odors, the dogs’ heart rates went up and they sought comfort from their owners. This led researchers to conclude that not only can dogs smell our emotional state, they also tend to take on those emotions as their own.

5. Using The “It” Factor

Until 2019, scientists could not explain how dogs sensed impending seizures in humans. They had no doubt they could do it, they just could not pinpoint exactly what it was the dogs see, hear, smell, or feel to tip them off.

While this mystery has been solved, there are still some incredible ways dogs sense our emotions that we don’t fully understand. Call it a sixth sense or an “It” factor.

The most striking example is our dogs’ uncanny ability to sense “bad” people or those with ill intentions. We all know that dogs tend to be excellent judges of character, but how do they do it?

The truth is, scientists aren’t quite sure. It could be simple instinct, or maybe dogs pick up on nervous energy radiating from these unsavory characters.

Most likely it has something to do with their incredible noses. When a person behaves aggressively, their brain chemistry changes. D ogs may be able to smell these changes and sense their intentions.

If this is the case, even our dogs can’t save us from a psychopath. Since they experience fewer emotions, their brain chemistry is unlikely to alert our dogs to their cruel intentions.

Has your dog ever alerted you to a dangerous person, helped detect a health problem, or identified exactly how you were feeling? Let us know in the comments!

Can Dogs Smell Fear?

Have you ever noticed that when you are feeling fearful, your dog becomes more attentive and clingy?

Have you also noticed that your dog may behave differently around people who like dogs versus people who are afraid of dogs?

Dogs have an incredible sense of smell, but can they smell fear? And if so, how?

Is It True That Dogs Can Smell Fear?

The science is in, and the answer is a resounding YES—dogs can smell fear. Dogs have olfactory superpowers that can detect a human’s emotional state by the scent that a human emits. That’s right—you can’t hide fear from dogs. They’ve got your number!

Until recently, the idea that dogs can smell fear was only a theory, but a study called “Interspecies transmission of emotional information via chemosignals: from humans to dogs” actually proves that dogs (or at least Golden Retrievers and Labrador Retrievers) can smell human emotions and respond accordingly.

When a person gets scared, their sweat glands will start secreting moisture, especially in the armpits. This sweat contains chemical signals that dogs can pick up on.

Can Dogs Smell the Difference Between Fear and Happiness?

Researchers correctly postulated that dogs would respond differently to human odors that were emitted under different emotional states—namely, fear and happiness.

In the study, dogs were exposed to three stimuli—their owner, a stranger (the control) and an odor dispenser. Dogs were assigned to different odor conditions randomly.

They collected odors from humans in three different emotional states: fearful, happy and neutral (no sweat). The odors were collected from the armpits of random male donors who were not otherwise involved in the experiment procedures.

The dogs were then observed for responses, including behaviors directed at the three targets, stress behaviors and heart rate. Researchers found that when the dogs were exposed to “happy odors,” they interacted more with the stranger and had lower heart rates.

In contrast, when the dogs were exposed to the “fear odor,” they displayed more stress behaviors and had higher heart rates associated with the fight, flight or freeze response—a bodily response of the autonomic nervous system that is essential for adaptation and survival.

The dogs also sought more reassurance from their owners and interacted with the stranger less than the dogs that were exposed to the “happy odor.”

Researchers concluded that chemosignals—odors that we emit in response to our emotional state—communicate across species to dogs. So, if we are scared, they can smell it and get scared, too.

What Your Dog’s Senses Can Tell You About Your Own Emotions

Dogs can help us recognize our own emotional states. Many people who have chronic anxiety may not even be aware that they are walking around in fight, flight or freeze mode.

A dog that’s in tune with how you exhibit stress or fear can help signal the onset of these emotions and help you better work through feelings of anxiety.

It’s also important to acknowledge that dogs can feed off of your energy. So, try to temper your mindset throughout tense situations—say, like at your next vet visit—to help keep your pet more at ease.

Your mental health and that of your pet are both important. If you take note of how your dog is behaving, you might learn more about your own mood and mental state than expected.

By: Dr. Sarah Wooten

Featured Image: iStock.com/Marsco Roasario Venturini Autieri

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Can Dogs Smell Fear? (What Science Tells Us)

If you’ve noticed that your dog becomes clingy and attentive to you when you’re afraid, you’re not imagining it. It’s the same “sixth sense” that causes dogs to behave differently around people who are afraid of them. We know that dogs have an amazing sense of smell, but can they actually smell fear?

The short answer is yes, there’s scientific evidence that dogs can smell fear. Keep reading to learn how this works!

Can Dogs Smell Fear? What the Science Says

There is, in fact, scientific evidence that proves that dogs can smell fear. Dogs have smell superpowers that give them the ability to detect human emotional states by their scent. You can’t hide your fear from dogs, and they know if you’re faking it!

A study conducted in 2017 called “Interspecies transmission of emotional information via chemosignals: from humans to dogs” proved that dogs could smell human emotions and respond accordingly.

When a human feels scared, they emit moisture from their sweat glands. Sweat contains a variety of different chemicals that dogs can smell.

What Emotions Can Dogs Smell?

Dogs respond differently to humans in different emotional states, primarily fear and happiness. Dogs that are exposed to “happy smells” have lower heart rates and higher levels of interaction.

When dogs are exposed to a fearful human, they exhibit stress behaviors, like higher heart rates and freeze responses. They also seek more reassurance from their owners than dogs who are exposed to happy odors.

Researchers believe that the emotional states that we emit to our dogs directly communicate across species. So, if we’re scared, our dogs become scared too.

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How Powerful Is a Dog’s Nose?

Dogs have as many as 300 million olfactory receptors in their noses, compared to only 6 million found in a human nose. On top of this, the portion of a dog’s brain devoted to smell is 40 times greater than ours.

Dogs can smell substances at a concentration of one part per trillion, the equivalent of one drop of liquid in an Olympic-sized swimming pool. With the right training, dogs are capable of sniffing out bombs and drugs, tracking missing people, finding dead bodies, and even detecting disease. Cancer, diabetes, tuberculosis, and malaria are all able to be sniffed out by dogs, even without the human exhibiting symptoms.

How Your Dog’s Senses Can Help You Manage Your Emotions

Dogs are fantastic at helping us recognize our emotional states. Chronic anxiety, for example, can lead to walking around in a constant “fight or flight” state. It creates an over-activated nervous system, increased heart and respiratory rates, and an overall state of stress in the body.

The fact that dogs are so in tune with this can be helpful in recognizing the onset of strong emotional states and cue us to work through our feelings. This awareness can also help our dogs. Since they feed off our emotions, changing our mindset during intense situations (like vet visits) can help our dogs feel more relaxed.

It’s important for both humans and dogs to maintain mental health, and the two may be connected more than we think.

Featured Image Credit: Aleksey Boyko, Shutterstock

Chelsie is a freelance writer who is passionate about helping owners and pets live their best lives. She resides in rural Alberta, Canada with her husband and two sons, and is currently a pet parent to four horses, four cats, and a border collie.