Dogs can smell and detect stress from human sweat and breath.
- Anxiety disorders are twice as prevalent in women as in men.
- This discovery may help to better train service and therapy dogs so that they know when their handler is under pressure.
“Previous research suggests that dogs can tell when humans are under stress,” said researchers from Queen’s University of Belfast in Northern Ireland. To find out for sure, they carried out a study, the results of which were published in the journal Plos One. In the latter, they tested whether dogs were able to distinguish between classic odors and stress-related odors.
Dogs managed to smell stress-related odors
To carry out their work, the scientists recruited 36 people and four dogs. They took sweat and breath samples from participants before and after they solved a difficult math problem. The volunteers were also asked to indicate their level of stress before and after the task.
Next, the team taught the dogs to recognize stress-related odors and then had them smell the samples taken just four minutes apart, before and after the stressful state. All of the four-legged animals were able to smell and detect the samples where the person’s blood pressure and heart rate had increased.
Stress produces “changes in organic compounds”
“The results indicate that physiological processes associated with an acute psychological stress response produce changes in organic compounds emanating from breath and/or sweat that are detectable by dogs,” the authors said. “This research shows that dogs do not need visual or auditory cues to detect stress in humans. This is the first study of its kind,” they added in a statement.
