On Wednesdays, we wear… diapers? Puh, Mean Girls.
This is Sandra Tsing Loh with the Loh Down on Science.
A healthy gut contains a diverse ecosystem of bacteria! But – where do we get it from?
Enter Liviana Ricci and team at the University of Trento, Italy.
They studied a thousand stool samples from babies and their families. P-U!
Now here’s the poop on that. Initially, babies acquired twenty-four percent of bacterial strains from their families. But after three months in nursery, strains acquired from classmates INCREASED more than four-fold!
These babies now had more in common with their peers than families, fecally speaking.
Turns out in daycare, you can’t sit with us… without sharing microbes! Brown is the new pink!
Reference: Ricci, L., Heidrich, V., Punčochář, M. et al. Baby-to-baby strain transmission shapes the developing gut microbiome. Nature (2026).https://doi.org/10.1038/s41586-025-09983-z