Scientists in Italy have discovered lactic acid bacteria in fermented food transfers to the gut microbiome. Though this is a widely accepted health benefit of fermented foods, there is little scientific research linking fermented food and the microbiome. The study looked at distribution of lactic acid bacteria (LAB) in humans based on location, age and lifestyle.

LAB genomes were reconstructed from about 300 foods and nearly 10,000 human fecal samples from humans from different continents. 
The most frequent LAB food in the human feces: streptococcus thermophilus and lactococcus lactis, commonly found in yogurt and cheese. 

“Our large-scale genome-wide analysis demonstrates that closely related LAB strains occur in both food and gut environments and provides unprecedented evidence that fermented foods can be indeed regarded as a possible source of LAB for the gut microbiome.”

Read more (Nature Communications)