friendship Often triggered by shared interests, hobbies or experiences, but could our gut microbiome also play a role? A Yale study recently published in Nature reveals a surprising connection: People within the same social network share similar gut microbiomes, suggesting that our social bonds can affect us at the microbial level.

The microbiome, which includes the bacteria, fungi, and other microorganisms living in the digestive tract, has long been studied for its effects on health. However, this research takes a new approach, exploring how our social interactions may shape the structure of these microbial communities.

The study analyzed the gut microbiomes of 1,787 adults in 18 different villages in Honduras, examining 339,137 microbial strains. The researchers found that people in the same social network – whether they live together or not – share similar microbiomes.

“We found substantial evidence of microbiome sharing between people who are not family and who do not live together, even after taking into account factors such as diet, water sources and medications,” said co-lead author Francesco Beggini. “In fact, in the villages we studied, microbiome sharing was the strongest predictor of people’s social interactions, beyond characteristics such as wealth, religion, or education.”

Microbial similarities were most pronounced between cohabitants, partners, and household members. However, the study also revealed significant microbial sharing between friends and even second-degree connections, such as friends of friends. Shared activities such as eating together or physical interactions such as handshakes and hugs likely facilitated this microbial exchange.

People outside the social network, despite living in the same village, displayed little similarity in their gut microbiomes.

To confirm these findings, the researchers revisited the four villages two years later, and re-examined the microbiomes of 301 participants. Their results showed that socially connected individuals became more similar in their microbial compositions, lending credence to the idea that social bonds promote microbial similarity over time.

Interestingly, the study also identified specific microbial strains clustered within social groups. These strains were distinct from strains found in other groups, indicating that shared social activities contribute to unique microbial communities.

“You have friend groups focused on things like theater, or crew, or being a physics major,” said co-lead author Jackson Pullman. “Our study indicates that the people who form these clusters may be connected in ways we never thought about before, even through their microbiomes.”

Get the latest news live on Times Now with breaking news and top headlines from around the world.