Feeling stressed? Your dog probably smells it

Who else likes to think that our dogs can read our emotions just as well as we can read theirs? They're our best friends, after all. Well, we’re right — a new study confirms that dogs can tell changes in people's feelings, like when one becomes stressed. 

Four dogs in 36 sessions analyzed 36 people in the study. First, researchers took people's sweat and breath samples when relaxed and then again after a challenging mathematics problem. Next, the pups were shown how to sniff the samples, and then they were asked to lead researchers to the stress versions. In each instance, all dogs sniffed the stressed scents. 

‍Can dogs smell fear? 

According to Dr. Emily Singler, VMD, Fetch’s on-staff veterinarian, researchers have known that dogs can tell differences in our bodies by how we smell. For example, they can detect oncoming seizures, low blood sugar, multiple cancers and infections like COVID-19. However, this study proves another ability of dogs.

“This study states that it’s the first one to confirm that dogs can tell the difference between samples from stressed individuals and non-stressed individuals,” Dr. Singler says. “Previously, researchers knew that dogs could detect human emotions based on humans' behavior and facial expressions. Other studies have suggested that animals could detect stress in humans based on smell, but this study further showed that dogs can differentiate between stressed and non-stressed samples.”

And these findings weren’t just a benefit to the research team. “This study can suggest new ways to help train service dogs or emotional support dogs to help alert parents when they’re about to have a panic attack so that they can seek help or engage in calming techniques to lower their stress,” Dr. Singler shares. “Similar to how some dogs alert their parents to an impending seizure or low blood sugar levels.”

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Dogs’ keen sense of smell isn’t the only way they can pick up on stress. Your facial expressions, body language, tone of voice and behavior, along with any changes in your routine, also let your pup know you’re feeling anxious, Dr. Singler explains. You might appreciate it when your dog matches your mood (there’s nothing better than having a partner in crime to equal your snuggles), but they can actually become stressed when you’re feeling that way, too. 

“Our stress level does affect dogs. Studies have shown that when humans have high blood cortisol levels (which is the body's stress hormone), their dogs also tend to have high cortisol levels,” Dr. Singler says. “This means that dogs can become stressed when their parents are stressed.” 

Shared stress can cause mixed reactions in our dogs, Dr. Singler says. For example, some pups become fearful or aggressive, while others might try to comfort you. And in the spirit of mirroring each other’s behaviors, calming yourself down in stressful situations can also help to relax your pup.

“When we calm ourselves, dogs will be able to detect the change and become calmer as a result,” Dr. Singler encourages. “Other ways to help reduce stress in dogs include regular exercise and mental stimulation. Some dogs with high-stress levels, particularly those prone to anxiety, will benefit from vet-prescribed supplements and/or medication to lower their anxiety and stress.”

Thanks to the recent study, we now understand that dogs love their people more than we even knew — so much so that they're willing to recognize and take on our stress.