Key points from article :
People who live to age 100 and beyond may have special gut bacteria that help ward off infections.
Examined the gut microbiota of 160 centenarians (average age, 107 years).
Centenarians had a distinct signature of gut microbes and significantly higher levels of secondary bile acids.
Found particularly high levels of a secondary bile acid called isoallolithocholic acid (isoalloLCA).
IsoalloLCA may contribute to a healthy gut by preventing the growth of bad bacteria.
"They might one day be used as a probiotic to improve human health," - Kenya Honda, senior author.
These bacteria appear safe, as they don't produce toxins or harbor antibiotic-resistance genes.
"Genetics and diet could play a role in shaping the composition of people's gut microbiota," - Honda.
Future studies on large groups of people could further probe the link between these bacteria and longevity.
Study by Keio University School of Medicine published in the journal Nature.
