People who live to 100 have unique gut bacteria signatures - Livescience.com

People who live to age 100 and beyond may have special gut bacteria that help ward off infections, according to a new study from Japan.

The results suggest that these bacteria, and the specific compounds they produce — known as "secondary bile acids" — could contribute to a healthy gut and, in turn, healthy aging.

"Although it might suggest that these bile-acid-producing bacteria may contribute to longer life spans, we do not have any data showing the cause-and-effect relationship between them," Honda told Live Science.

The community of bacteria and other microorganisms that live in the gut, known as the gut microbiome, is known to play a role in our health and changes as we age.

But researchers suspected that people who reach age 100 may have special gut bacteria that contribute to good health.

The researchers then analyzed gut metabolites (products of metabolism) in all three groups, and found that centenarians had significantly higher levels of so-called secondary bile acids compared with the other two groups.

After the liver produces bile acids, they are released into the intestine, where bacteria chemically modify them into  secondary bile acids, according to a 2009 paper published in the journal Diabetes Care.

They screened gut bacterial strains from a 110-year-old who had particularly high levels of secondary bile acids and found that bacteria belonging to a family called Odoribacteraceae produced isoalloLCA.

IsoalloLCA also inhibited the growth of vancomycin-resistant enterococci, a type of antibiotic-resistant bacteria known to cause infections in hospital settings.

The findings suggest that isoalloLCA may contribute to a healthy gut by preventing the growth of bad bacteria.

They also suggest that these bacteria or their bile acids could treat or prevent C.

If these bile-acid-producing bacteria do contribute to a healthy gut, they might one day be used as a probiotic to improve human health, Honda said.