Our gut bacteria can play a role in everything from sleep to IBS and how we deal with stress, and we are finally working out how to use them to improve our health
In the last 10 years, interest in the microbiome – the vast colonies of bacteria and other organisms living in our digestive system – has intensified, including its possible role in gut complaints such as irritable bowel syndrome. Studies have shown that the faecal microbiota of people with IBS differs significantly from those of people who don’t have it. Some suggest that a course of antibiotics raises the risk of developing a functional gut disorder like IBS – another hint that an imbalance in gut bacteria might be involved.
Some scientists now believe that this imbalance or “dysbiosis” seen in IBS affects the immune and nervous systems, driving people’s symptoms and the way the brain perceives them.
An unhealthy microbiome might even play a role in the fact that people with IBS are more prone to certain psychological problems such as stress, which in turn seems to further exacerbate their IBS symptoms.
A recent study that transplanted the microbiota of humans with IBS into mice found that the mice showed not only physical symptoms associated with IBS, such as faster transit of food through the gut and an altered immune response, but behavioural ones too, such as anxiety.
The hope is that treating dysbiosis in people with IBS, for example by using probiotics that seed the gut with “friendly” bacteria, could provide relief. The jury is still out, however, on whether probiotics really work. According to one recent study, they could actually prevent bacteria recolonising the gut after a course of antibiotics. Still, for IBS patients, they might help, says …