Gut microbiome could be linked to depression

LEUVEN, BELGIUM — A new study of two large groups of Europeans has found several types of gut bacteria are missing in people with depression, according to Science Magazine.
The scientists could not say whether the absence is a cause or an effect of the illness, but were able to show that many gut bacteria could produce substances that affect nerve cell function and possibly mood. The results were published in the journal Nature Microbiology.
To test the link between the microbiome and depression, Jeroen Raes, a microbiologist at the Catholic University of Leuven in Belgium, and his team looked at 1054 Belgians to assess a "normal" microbiome.
Within the group, 173 people had been diagnosed with depression or done poorly on a quality of life survey. The gut microbes of depressed group was then compared to the "normal" group.
Two types of bacteria, Coprococcus and Dialister, were absent from the guts of depressed participants.
The team then looked at the microbiomes of 1064 Dutch participants and also found the same two species were missing in people who were depressed.
It is still unclear how the gut microbiome affects the brain. One possible avenue is through the vagus nerve, which connects the gut and the brain.
But with more studies, scientists hope the microbiome-brain connection could eventually lead to novel therapies for treating depression.