Hello readers: I’ve come across an interesting article from my own home university, the University of Guelph! It’s entitled “Stress and the microbiome: linking glucocorticoids to bacterial community dynamics in wild red squirrels“, and it’s fascinating because (a) wild animals were used, responding naturally to their environments, and (b) it shows a direct link between levels of stress, as measured by faecal glucocorticoid hormones, and the microbiome, which controls so many aspects of one’s health. The paper comes out of the lab of Amy E. M. Newman.
The analysis is a little crude- the authors only looked at diversity of bacteria in faecal samples, not composition of bacteria to find which bacteria changed in abundance with stress- but it’s very clear that the overall diversity of bacteria in the microbiome of the squirrels analyzed in the study (via collection of faecal pellets) dropped when those pellets had higher levels of glucocorticoid hormones (which are an indicator of stress response).
What does this mean for you? Well, it’s clear from many studies that stress negatively impacts your health, and the alteration of the gut microbiome in response to stress probably happens in people as well as squirrels. This may be one more mechanism by which our psyche is connected to our physiological state via the gut-brain axis.