The closer scientists look at bacteria in the gut, the clearer their importance to our overall health becomes, and new research links a particular type of gut microbiome development to longer life expectancy and healthier old age. .
In a study of more than 9,000 people in three different cohorts, new research has found that our gut microbiomes become more unique and personalized to us as we age, and that the number of core bacteria (such as Bacteroides) tend to decrease as well.
This pattern also appears to be associated with physical health and longevity. So people whose microbiomes don’t continue to change into old age, and who don’t see a reduction in core bacteria, tend not to be as healthy or live that long.
“This uniqueness signature can predict patient survival into the last decades of life,” says biochemist Tomasz Wilmanski of the Institute for Systems Biology (ISB).
“Interestingly, this pattern of uniqueness appears to start in middle age, between 40 and 50 years old, and is associated with a clear metabolomic signature of the blood, suggesting that these changes in the microbiome may not simply be a diagnosis of healthy aging. They can also directly contribute to health as we age. “
It was remarkable that even when microbiomes diverged in design at older ages, the metabolic functions they performed were consistent across individuals: the researchers found certain longevity-related metabolites in the gut of people (and various animals) whose microbiomes followed a healthier evolution. Pattern.
As Wilmanski points out, the question remains whether these changes in the composition of the microbiome are really contributing to good health or just reflecting it, but it is certainly worth more research, scientists say, and adds some clarity to an area of research. in which the findings have not always been clear.
For example, metabolites called indoles were discovered that had previously been linked to reduced inflammation in the gut of mice, and chronic inflammation is one of the health problems known to increase mortality risk in older people. .
“Previous results in microbiome aging research appear inconsistent, with some reports showing a decline in central gut genera in centennial populations, while others showing relative microbiome stability until the onset of declining health related to aging, “says ISB microbiologist Sean Gibbons.
“Our work, which is the first to incorporate a detailed analysis of health and survival, can resolve these inconsistencies.”
While the study as a whole covered people between the ages of 18 and 101, it was a particular cohort of people between the ages of 78 and 98 that allowed the researchers to take a closer look at how microbiomes and mortality might be linked.
We know that it’s at the beginning and end of our lives that our gut bacteria mix goes through the most important changes, and this latest study supports the idea that a continuously evolving mix of belly bacteria at the end of life is a good sign. : perhaps it is an indicator of a still prosperous body in the last years of life
The study suggests that a healthy gut microbiome, whatever it is, may not look the same at different stages of life, and that’s a useful avenue to explore in future research. It seems that our microbiomes can develop in different ways in older people, and some of those developments may be healthier than others.
“This is exciting work that we believe will have important clinical implications for monitoring and modifying the health of the gut microbiome throughout a person’s life,” says ISB bioengineer Nathan Price.
The research has been published in Nature’s metabolism.