Dogs have been humans’ loyal companions since early in human history, with the earliest evidence showing that dogs have been our pets for over 12,000 years. It’s safe to say that with that much time, dogs have become uniquely accustomed to humans, and a study published in the journal Scientific Reports makes it clear just how deep that bond is. The study shows that not only can dogs identify the odor caused by the stress hormone cortisol, but that smell of stress affects their emotional state resulting in different behaviors. 

How our own emotions influence our dogs

Research has long proven that dogs are able to detect minute differences in odor with their highly acute sense of smell. In fact, some dogs are even trained to sniff out cancer or imminent hypoglycemia. But even dogs whose only job is to be a beloved pet have this excellent sense of smell, so they can tell just by scent when we’re experiencing stress. This change in our scent is caused by a rise in cortisol levels, and can be detected in our sweat. While dogs’ keen sense of smell is well-known, researchers at the University of Bristol in England were interested in examining how a human’s stress might affect a dog’s emotional state and behavior. The study took sweat samples from volunteers in both a stressed and relaxed state, and dogs were trained at a task designed to measure their degree of optimism. The dogs didn’t know the volunteers, eliminating the variable of familiarity. Nonetheless, the dogs performed the trained task more pessimistically when they were exposed to the stress scent. This shows that our moods can influence dogs and their behavior. 

Is it bad for dogs to be exposed to stress?

if you’re a dog owner, you already have a good idea of how in tune dogs are with their owners’ emotions as well as their own. The study shows that dogs’ emotional responses and behaviors can change if they sense their owner is dealing with stress.

What does this mean for pet owners? 

If you’re feeling stressed, the best thing you can do is to avoid playing with or training your dog until you’ve had some time to relax. Otherwise, you may be inadvertently worrying your pet. Maintain a relationship based on positive reinforcement by rewarding your dog for the behaviors you want. If you’re in an upbeat, positive mood when you’re training and playing with your dog, you’ll also be building their confidence. Of course, relaxing with your dog is also a great way to alleviate your own stress, so remember your dog can take care of you too.Â