Under stress? Your breath could tell!
Deep breathing, recommended for stress busting, could also be used to understand whether or not you are under stress, scientists say.
There are six markers in the breath that could be candidates for use as indicators of stress, according to a new study published in Journal of Breath Research.
The researchers hope that findings such as these could lead to a quick, simple and non-invasive test for measuring stress; however, the study, which involved just 22 subjects, would need to be scaled-up to include more people, over a wider range of ages and in more "normal" settings, before any concrete conclusions can be made, they state.
"If we can measure stress objectively in a non-invasive way, then it may benefit patients and vulnerable people in long-term care who find it difficult to disclose stress responses to their carers, such as those suffering from Alzheimer's," lead-author of the study, Professor Paul Thomas, said.
The study, undertaken by researchers at Loughborough University and Imperial College London, involved 22 young adults who each took part in two sessions: in the first, they were asked to sit comfortably and listen to non-stressful music; in the second, they were asked to perform a common mental arithmetic test that has been designed to induce stress.
A breath test was taken before and after each session, whilst heart-rates and blood pressures were recorded throughout. The breath samples were examined using a technique known as gas chromatography-mass spectrometry, and then statistically analysed and compared to a library of compounds.
Two compounds in the breath - 2-methyl, pentadecane and indole - increased following the stress exercise which, if confirmed, the researchers believe could form the basis of a rapid test.
A further four compounds were shown to decrease with stress, which could be due to changes in breathing patterns.
"What is clear from this study is that we were not able to discount stress. It seems sensible and prudent to test this work with more people over a range of ages in more normal settings," he said.
