A shared meal, a kiss on the cheek: these social acts bring people together — and bring their microbiomes together, too. The more people interact, the more similar the make-up of their gut microorganisms is, even if individuals don’t live in the same household, a study shows.

The study also found that a person’s microbiome is shaped not only by their social contacts but also by the social contacts’ connections. The work is one of several studies that raise the possibility that health conditions can be shaped by the transmission of the microbiome between individuals, not just by diet and other environmental factors that affect gut flora.

What if we shared our microbiomes under the moonlight

Associated research article (open access): Beghini, F., Pullman, J., Alexander, M. et al. Gut microbiome strain-sharing within isolated village social networks. Nature (2024). https://doi.org/10.1038/s41586-024-08222-1

Another relevant research article cited by the news (also open access): Valles-Colomer, M., Blanco-Míguez, A., Manghi, P. et al. The person-to-person transmission landscape of the gut and oral microbiomes. Nature 614, 125–135 (2023). https://doi.org/10.1038/s41586-022-05620-1