Potential Link Between Gut Bacteria Groups and Insomnia Risk Identified in New Study

Recent research suggests a complex, bidirectional relationship between certain gut bacteria and the risk of developing insomnia. A study published in the open-access journal General Psychiatry utilized Mendelian randomization analysis to investigate the influence of gut microbiome composition on sleep disorders. By analyzing genetic data from over 386,000 individuals with insomnia and comparing it with gut microbiome information from thousands of participants in the MiBioGen and Dutch Microbiome projects, researchers uncovered significant associations.

The study identified 14 groups of bacteria whose increased presence slightly raised the odds of insomnia, while eight others appeared to have a protective effect, lowering the risk. Interestingly, insomnia itself was associated with marked fluctuations in the abundance of several bacterial groups, showing between 43% and over 400% variations. Notably, the Odoribacter class of bacteria was prominently linked to sleep disturbance.

Importantly, the study found no evidence of pleiotropy, reinforcing the likelihood of a causal connection between gut bacteria and insomnia. However, the researchers caution that their findings are primarily based on data from individuals of European descent, meaning further research across diverse populations is essential. The interplay between insomnia and gut microbiota involves complex pathways such as immune modulation, inflammatory responses, and neurotransmitter release.

The implications of this research are significant, opening potential avenues for microbiome-based treatments like probiotics, prebiotics, or fecal microbiota transplants aimed at alleviating insomnia. These findings add to the growing body of evidence that our gut health profoundly impacts sleep quality and overall mental health.

Source: https://medicalxpress.com/news/2025-08-reciprocal-links-groups-gut-bacteria.html