Bacteria living in the human intestine are associated with depression

With the mental state, some bacteria living in the human gut appear to be related to Belgian scientists.

The new research found for the first time that two types of microorganisms are found in much lower levels in depressed individuals than in those with good mental health.

The relationship between microbes and mental health has been the subject of scientific debate for some years now. The new study comes to reinforce suspicions that the existence or absence of certain bacteria is somehow involved in the mental state of at least some people. Probably this is due to the fact that bacteria produce substances that affect the chemistry of the brain and consequently the emotions and behavior.

The researchers, led by Professor Geroen Rays of the Catholic University of Leuven and the Flemish Institute of Biotechnology, who studied two groups of 1,054 Belgians and 1,064 Dutch (some with diagnosed depression), made the publication in the journal Microbiology “Nature Microbiology” , according to “Science”, Guardian and Indepedent.

Scientists have discovered that two types of bacteria (Coprococcus and Dialister) are at significantly lower levels in the gut of depressed people, whether they are taking antidepressants or not, irrespective of their age and gender.

This finding does not prove that intestinal microbes do in fact adversely affect mental health, as vice versa, namely depression to favor certain bacteria, while others can not. However, the new study shows that bowel bacteria “talk” with the human nervous system, affecting substances (neurotransmitters) such as dopamine and serotonin, which play a vital role in mental health and are involved, among others, in the development of depression .

If confirmed by future research that the low levels of these bacteria are responsible – at least to a degree – for depression, then the pathway for probiotic and other therapies that will strengthen the populations of these microorganisms in the intestine opens. But until tests are done on humans, animal studies should be preceded, so it will take quite a while.

Another British-Australian scientific group, who published the journal Biotechnology magazine “Nature Biotechnology”, announced that it has discovered over 100 previously unknown bacterial species of healthy human intestine. The study, based on faecal genetic analysis, brought to light 273 different bacterial species, of which 105 were isolated for the first time.

The new findings are the most comprehensive list of intestinal microbes that has been implicated in a variety of disorders such as irritable bowel syndrome, allergies, obesity and, apparently, mental disorders.

Approximately 2% of a person’s body weight is due to the host bacteria. The largest microbial ecosystem is located in the intestine, where trillions of microbes live.