Dogs can smell stress, study finds
"This is the first study of its kind" - Clara Wilson.
Researchers from Queen's University Belfast have discovered that dogs can detect the scent of stress on humans.
Studying four dogs from Belfast and 36 people, researchers found that there was an odour difference in samples of sweat and breath when participants were stressed, compared to when they were relaxed.
The researchers taught the dogs to search a scent line-up, and to alert researchers to the correct sample.
Not knowing whether there was a detectable odour difference in the samples collected, the researchers gave each dog one person's relaxed and stressed samples – and all of the dogs were able to correctly alert researchers to each person's stress sample.
Clara Wilson, PhD researcher in the School of Psychology at the university, explained: “The findings show that we, as humans, produce different smells through our sweat and breath when we are stressed and dogs can tell this apart from our smell when relaxed – even if it is someone they do not know."
“The research highlights that dogs do not need visual or audio cues to pick up on human stress. This is the first study of its kind and it provides evidence that dogs can smell stress from breath and sweat alone, which could be useful when training service dogs and therapy dogs.
“It also helps to shed more light on the human-dog relationship and adds to our understanding of how dogs may interpret and interact with human psychological states.”
Carried out by Clara Wilson (PhD researcher) and Kerry Campbell (MSc student), the study has been published in PLOS ONE.
The BSAVA has opened submissions for the BSAVA Clinical Research Abstracts 2026.
