Bama County, a rural area in China, is home to a significant number of individuals who live to be over 100 years old, so-called centenarians. Why is it that people who live in this region have a much greater chance of living to be over 100 than almost anywhere else in the world? It is largely unknown however many people have hypothesized that while it may partly be genetic, lifestyle plays an important role in these people living longer lives.
Scientists in China set out to study the microbiome of individuals in this county and find associations between age and diet. 8 centenarians between 100-108 from rural Bama County, 8 elderly individuals between 85-99 from Bama County, and 8 elderly individuals between 80-92 from Nanning, a Chinese city in the same region as Bama, each provided stool samples as well as detailed long-term dietary information.
The researchers found that centenarians had greater diversity of bacteria in their guts compared to the younger elderly individuals. They also found several bacterial species that were more or less abundant in centenarians than the other elderly from both rural and urban environments. While some of these results were not in line with previous studies, the results did indicate that age played an important role in shaping the microbiome.
They also found that there were specific bacteria that were more or less abundant in the study participants living in rural areas who ate a diet with more fiber than those elderly living in an urban environment who ate a diet with less fiber. These findings suggest that both age and a high-fiber diet can help establish a gut microbiota that promotes beneficial health. These studies were only conducted on 24 individuals with 8 people in each study group and therefore significantly more work will need to be done to better understand if and how the microbiome is playing a role in elongating the lives of these centenarians.