Gut bacteria may have impact on mental health, study says
Jeroen Raes of the Flanders Institute for Biotechnology and the Catholic University of Leuven drew on medical tests and GP records to look for links between depression, quality of life and microbes lurking in the faeces of more than 1,000 people enrolled in the Flemish Gut Flora Project.
The study reported in Nature Microbiology does not prove that gut microbes affect mental health. It is possible that the effect works the other way around, with a person’s mental health having an impact on the bugs that thrive inside them. But in follow-up experiments, Raes and his team found evidence that gut microbes can at least talk to the human nervous system by producing neurotransmitters that are crucial for good mental health.
“We studied whether gut bacteria in general would have a means to talk to the nervous system, by analysing their DNA,” he said. “We found that many can produce neurotransmitters or precursors for substances like dopamine and serotonin.” Both dopamine and serotonin have complex roles in the brain and imbalances have long been linked to depression.