Do Dogs Know When You’re Stressed?

According to Dr. Zoe Parr-Cortes, veterinarian and PhD graduate from the University of Bristol, research studies support the idea that dogs can sense stress in people. “As one of our closest companions, dogs have co-evolved alongside humans for thousands of years. Because of this, both humans and dogs have learned to recognize cues in each other that signal how the other is feeling. Several studies have demonstrated that dogs respond to the sights and sounds of various human emotions, including crying, vocal tones, and facial expressions.”

For example, scientists have shown that your dog can hear your mood in the tone of your voice. The sounds of happiness are likely to result in a positive reaction, like tail wagging, whereas sadness and fear can result in a negative reaction, like yawning. And research in the journal Biology Letters showed that dogs have the ability to match your mood to the look on your face. So if dogs know when you’re happy or sad, it makes sense that they can sense your stress, too.

How Do Dogs Sense Your Stress?

Dr. Parr-Cortes says dogs can sense stress based on a combination of cues and the context of the situation. They can observe your facial expressions and body language and listen to the tone of your voice. And of course, dogs have powerful noses that can detect changes in how we smell. “When we’re stressed, we act and communicate differently, and our dogs will notice this. However, while sight and sound may be more obvious for us to recognize as cues, smell is a sense that is much more important to dogs than humans,” she explains.

Research published in PLOS One showed that dogs can detect stress from sweat and breath samples alone. For the study, human participants provided baseline sweat and breath samples. Then, the researchers administered a math test to the participants, with the intention of causing them stress, before collecting a second set of samples. When researchers presented the samples to dogs, they could tell the difference between the baseline and stress samples with over 90% accuracy. It seems that acute stress changes what’s known as volatile organic compounds in breath and sweat. These compounds are detectable to dogs’ noses.

How Do Dogs Smell Stress?

So what exactly are the dogs smelling? That’s harder to pin down. In a recent study published in Scientific Reports, Dr. Parr-Cortes and other members of the Animal Welfare and Behaviour Group at Bristol Vet School stressed human participants with public speaking and an arithmetic test. To measure stress, the research group and its principal investigators, Dr. Nicola Rooney and Professor Mike Mendl, looked at the participants’ cortisol (a hormone released by the adrenal gland during times of stress), heart rate, and the participants’ own rating of anxiety levels. And of course, they collected sweat samples.

For the study, Dr. Parr-Cortes and her colleagues primarily selected samples from people with the highest cortisol response. They thought this would be a good marker to use because the charity Medical Detection Dogs has trained dogs to smell when the cortisol levels in people with Addison’s disease drop too low. And based on the current study’s findings, it seems that even untrained dogs may be able to detect differences in cortisol via scent.

To identify that potential stress smell, Dr. Parr-Cortes and members of Bristol Vet School are currently working on measuring the odor differences in the samples using volatile organic compound analysis. However, it’s possible dogs can detect subtle differences or patterns in odor that chemical analysis can’t.

Does Your Stress Impact Your Dog?

Although it aids survival, does your stress impact your dog’s well-being? Dr. Parr-Cortes’ study would indicate yes. It influences their emotions and the decisions they make. “We found that when the stress odor was present, dogs were less likely, and slower, to approach a bowl that they were uncertain contained a treat. This suggests that being stressed around your dog, or even just being around the smell of another person who is stressed, may have a negative effect on your dog’s mood and possibly even your relationship with your dog.”

Therefore, it’s important to appreciate the repercussions of human stress on a dog’s wellbeing, as well as on their learning and performance. “Maintaining a relationship based on positive reinforcement and engaging activities is the best way to keep your dog happy,” Dr. Parr-Cortes advises. Learn to spot your dog’s stress signals, keep calm around your dog, and consider doing a relaxing activity before interacting or training to reduce any effect your stress might have.

Image by Yama Zsuzsanna Márkus from Pixabay

By Stephanie Gibeault, MSc, CPDT

The busy spring and summer seasons can bring a sense of urgency and extra stress to our systems. While the demands of these seasons are unavoidable for many of us, we don’t have to suffer through stress-related symptoms in our bodies.

Taking just a few moments daily can build our resilience, no matter what challenges this season brings. Here are a few of my favourite “on-the-go” stress management and nervous system regulation tools.

Grounding

Think of your nervous system as a complex biological electrical circuit — one that benefits from being grounded. Grounding means connecting your awareness to the literal ground beneath you. This could be the earth itself, your floor, the floor of a vehicle, or the seat you’re sitting on. All these surfaces connect to our global electromagnetic field: the Earth.

While you may have seen ads for grounding products such as sheets, mats, shoes or clothing, all you really need is your mind and body. The simplest method is to notice where your body contacts a stable surface: your feet on the ground, your weight in a chair, or your back against a surface while lying down. That’s grounding!

Spending even a few moments in this awareness throughout your day effectively regulates your nervous system (that complex biological electrical grid) to the present moment. When we’re grounded in the present, we can better process past stresses and future worries.

Conscious breath

Taking a moment to focus on your breath is another powerful way to anchor yourself in the present moment and release lingering stress. Start by noticing the details of your breath: how it feels, where it moves. Then create a rhythm, making your inhales and exhales equal in length. You’ll likely find this rhythm becomes easier with practice. Next, try exhaling through an open mouth with a gentle sigh, gradually lengthening these exhales.

This breathing technique has been proven to calm your system and promote both regulation and rest. If you have trouble sleeping, this tool might be particularly helpful.

Sensory orientation

This practice engages your external senses: hearing, sight, smell and touch.

Begin by letting your eyes scan your environment: look up, behind, below and all around you. Take in as much detail as possible about your surroundings. Then let your gaze settle somewhere comfortable. Notice smells, starting with the strongest and moving to more subtle ones. Do the same with sounds. For touch, explore different textures with your hands, apply gentle pressure to various parts of your body, then slowly release. Finally, spend a few breaths mindfully feeling your feet against the ground.

Stress is a natural part of life, but our bodies aren’t designed to handle constant stress buildup. Regular self-care practices that support both body and mind are essential. Connecting with loved ones and community helps buffer stress’s impacts. If stress disrupts your sleep, relationships or overall well-being, it’s important to seek help from physical wellness and mental health professionals.

Image by Валентин Симеонов from Pixabay

Original Post 

About the author, Kathlyn Hossack is a certified athletic therapist and somatic therapist. She consults clients for injury rehabilitation and healthy lifestyles in person in St. Norbert, Man., and virtually via video conference.

Evidence in humans suggests that the smell of a stressed person subconsciously affects the emotions and choices made by others around them. Bristol Veterinary School researchers wanted to find out whether dogs also experience changes in their learning and emotional state in response to human stress or relaxation odors.

The team used a test of ‘optimism’ or ‘pessimism’ in animals, which is based on findings that ‘optimistic’ or ‘pessimistic’ choices by people indicate positive or negative emotions, respectively.

The researchers recruited 18 dog-owner partnerships to take part in a series of trials with different human smells present. During the trials, dogs were trained that when a food bowl was placed in one location, it contained a treat, but when placed in another location, it was empty.

Once a dog learned the difference between these bowl locations, they were faster to approach the location with a treat than the empty location. Researchers then tested how quickly the dog would approach new, ambiguous bowl locations positioned between the original two.

A quick approach reflected ‘optimism’ about food being present in these ambiguous locations—a marker of a positive emotional state—while a slow approach indicated ‘pessimism’ and negative emotion. These trials were repeated while each dog was exposed to either no odor or the odors of sweat and breath samples from humans in either a stressed (arithmetic test) or relaxed (listening to soundscapes) state.

Researchers discovered that the stress smell made dogs slower to approach the ambiguous bowl location nearest the trained location of the empty bowl. An effect that was not seen with the relaxed smell. These findings suggest that the stress smell may have increased the dogs’ expectations that this new location contained no food, similar to the nearby empty bowl location.

Researchers suggest this ‘pessimistic’ response reflects a negative emotional state and could possibly be a way for the dog to conserve energy and avoid disappointment.

The team also found that dogs continued to improve their learning about the presence or absence of food in the two trained bowl locations and that they improved faster when the stress smell was present.

Dr. Nicola Rooney, Senior Lecturer in Wildlife and Conservation at Bristol Veterinary School and the paper’s lead author explained, “Understanding how human stress affects dogs’ well-being is an important consideration for dogs in kennels and when training companion dogs and dogs for working roles such as assistance dogs.

“Dog owners know how attuned their pets are to their emotions, but here we show that even the odor of a stressed, unfamiliar human affects a dog’s emotional state, perception of rewards, and ability to learn. Working dog handlers often describe stress traveling down the lead, but we’ve also shown it can also travel through the air.”

Dr. Zoe Parr-Cortes, Ph.D. student at Bristol Veterinary School and primary author and researcher on the project expressed her thanks to everyone involved in the study, especially all the participants and dog owners who took part in the research.

For more information about stress and stress-related issues go to STRESS.ORG

Photo by Amal Santhosh

Conversely, social isolation, bereavement an inability to care for others and lack of zest for work and daily activities are associated with increased susceptibility to illness, depression, and loneliness. Caring for and looking after other living things, regardless of whether they are people, pets or plants seems to provide a powerful buffer against such problems by somehow promoting the healing ways of nature (vis medicatrix naturae).