Depression: intestinal bacteria could promote it

Researchers at the University of California, San Diego, USA, may have established the link between diet, genetics, microbiome bacteria and depression. Their work has been published in the journal Nature Genetics.

6000 volunteers observed for 16 years

They collected data on 6,000 volunteers from a large study in Finland, which began in 2002 and lasted until 2018. The volunteers had therefore been followed for their health for 16 years. The researchers used this data to study the genetics of the participants, their lifestyle, their diet, their consumption of drugs, their intestinal bacteria, etc.

Objective: better assess the role of diet and genetics on the microbiome. A field according to researchers for which there is “very few studies that have examined all of these factors in such detail“.

Two bacteria implicated

This work has enabled researchers to put their finger on two bacteria potentially responsible for depression in humans. It is morganella and Klebsiellawho “seemed to play a causal role” according to the researchers. One of them, Morganella, increased dramatically in the 181 people in the study who later developed depression, the scientists say.

This discovery “really is strong evidence that this association could be of major clinical importance.” according to Jack Gilbert, a microbial ecologist at the University of California, San Diego, who was not involved in the work.

Further investigations are needed

Since 2008, researchers have been working on the link between inflammation and depression and already the Morganella bacterium has been recognized as being involved in depression. So the latest study appears to be “further evidence” for Jack Gilbert, linking inflammation caused by gut bacteria and mood.

Research on these bacteria is still in its infancy, but scientists already believe that eradicating this bacteria will not be enough to cure depression.