The gut microbiota is linked to mental health disorders such as depression and schizophrenia

This post focuses on the gut-brain axis and the current status of research into the link between gut microbiota and mental health. Indeed, gut microbiota from humans with dep­ression, autism or schizophrenia can lead to behaviors linked to those mental health conditions in mice once transplanted with said human feces.


Using the gut microbiota as a potential target for discovering the bacteria involved in different mental health disorders

If you have experienced butterflies in your stomach when falling in love or nerves before starting a new job, then you have an idea about how your gut and brain are connected. The definition of the gut-brain axis has evolved in recent decades and the number of mental health disorders related to gut microbiota changes is on the rise.

Psychobiotics are one of the new alternative therapies that target the gut to help the brain. In order to develop a substance that targets the microbiome to help alleviate some mental health disorders, researchers need to find the bacteria involved in different mental health disorders.

A UK-based team led by Dr. Allan H. Young measured the microbial change taking place in studies focusing on depressive disorder, bipolar disorders, schizophrenia, anorexia, anxiety, obsessive-compulsive disorder, post-traumatic stress disorders, and hyperactivity disorders in order to identify a pattern visible across different mental health disorders worldwide.


Patients with some mental health disorders have a less diverse gut microbiota

Diversity is a parameter widely used in microbiota analysis and relates to the number of different species of bacteria present in the gut microbiota and their distribution. Repeated findings showed a lower number of species among patients with a mental health disorder, compared to healthy individuals.

Anti-inflammatory bacteria: the next psychobiotic?

The latest findings from Viktoriya Nikolova are that patients with depressive disorder, bipolar disorder, schizophrenia, or anxiety had a lower amount of beneficial bacteria-producing metabolites, such as short chain fatty acids, with anti-inflammatory properties compared to heathy individuals.

The changes, however, were found in a particular part of the world, with results from a Chinese cohort different to those from a Western European cohort. Moreover, changes in the gut microbiota were linked to the intake of medication related to different mental disorders. The results indicate that what can be true for one patient might not be for another, highlighting the importance of personalized medicine for each individual.

The study supports a better understanding of how the microbiome of a patient with a mental disorder is different from that of a healthy individual, to help develop future alternative therapies relating to the gut microbiota for treating mental health disorders.



Nikolova VL, Smith MRB, Hall LJ, Cleare AJ, Stone JM, Young AH. Perturbations in Gut Microbiota Composition in Psychiatric Disorders: A Review and Meta-analysis. JAMA Psychiatry. 2021 Sep 15:e212573. doi: 10.1001/jamapsychiatry.2021.2573. Epub ahead of print. Erratum in: JAMA Psychiatry. 2021 Nov 3;: PMID: 34524405; PMCID: PMC8444066.