Reference Number: 207
Year: 2008
Link: Link to original paper
Health: Stress
Summary
This study examined the impact of academic stress on salivary cortisol concentrations and lactic acid bacteria activity. Whole, unstimulated saliva samples and faecal samples were collected from 23 healthy undergraduate students (23.06.8 years; range 18–44) over two 1-week periods: during the beginning of semester (low-stress baseline condition) and during the first week of exams (high-stress condition). Students also completed a series of questionnaires measuring perceived levels of stress, gastrointestinal symptoms, and nutritional intake. Significant findings indicated that faecal lactic acid bacterial levels were lower during the high-stress condition. Paralleling this, students rated perceived levels of stress as being greater during the exam period compared to the baseline condition. The findings from this study have provided further insight into the link between stress and gastrointestinal flora activity in humans.
SIGNIFICANCE OF THIS STUDY
These results suggest stress may reduce the effectiveness of the gut microbiome in protecting against illness. But the authors also point out that factors such as diet and medication weren’t controlled for during the study, so changes in these may also have been affecting the microbiome rather than stress alone.