Dogs can smell when we are stressed out, say researchers

In the study, the dogs' accuracy at detecting the stress samples, from 90 per cent to 96.88 per cent, was better than expected. The researchers now hope that future studies investigate whether smell is an important part of a dog's perception of human emotions

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It is widely believed that dogs can detect extreme emotions by smell. Now, scientists at Queen's University Belfast, UK, have proved it. Acute stress changes the compounds found in human sweat and breath, research has shown. For the new experiment, four dogs were presented with sweat and breath samples collected from human volunteers before and after the people engaged in a difficult math exercise.