The gut-brain axis has been linked to moods and immunity, and further investigation into it has revealed that it’s far more complex and influential than previously believed. It sounds like a stretch, but scientists believe they have linked socioemotional traits of loneliness and wisdom to the diversity of gut bacteria itself.
Based on studies in the past which found a correlation between wisdom and loneliness, wise people felt lonely less often. Researchers from the University of California San Diego School of Medicine followed this correlation into studying how the bacteria in the gut communicates with the brain. It is understood that imbalances in the intestinal microbiome result in changes in the way the brain processes decisions, emotions, and regulates stress.
The study followed 187 participants who completed self-assessments about their reported loneliness and wisdom and asked them about the quality and quantity of the social support systems they have in place. Following the assessments, stool samples were analyzed to determine the composition of the bacteria populations present in their intestinal systems.
Interestingly, they found that those people who reported less loneliness and more social support had more diverse gut microbiomes than others. The researchers weren’t able to draw any direct conclusions about how these were linked just yet, but they noted that associated complications from having an imbalanced or poor microbial diversity could lead to downstream emotional effects which may lead an individual to feel lonely and therefore be less likely to reach out to their social supports.
The researchers also hypothesized that people with better gut health may be instrumental in strengthening the resilience of their communities because having this diversity meant better immune systems. It seems like there’s a sort of chicken-or-egg question that comes up from this study: was it because they were more social that they were exposed to more bacteria and therefore had a more diverse gut population—or was it the gut population they already had in place which made them more extroverted?
Tanya T. Nguyen, Xinlian Zhang, Tsung-Chin Wu, et al. Association of Loneliness and Wisdom With Gut Microbial Diversity and Composition: An Exploratory Study. Frontiers in Psychiatry, 2021; 12 DOI: 10.3389/fpsyt.2021.648475