The more scientists look at the bacteria in the gut, the clearer its importance for our overall health becomes, and new research links a certain type of development of the intestinal microbiome with a longer lifespan and a healthier old age. .
In a study of more than 9,000 people in three different cohorts, new research found that our gut microbiomes become more unique and personalized to us as we age and that the number of basic bacteria (such as Bacteroides) tend to decrease and.
This pattern also seems to be associated with physical health and longevity. So people whose microbiomes do not continue to change in old age and who do not see a reduction in the underlying bacteria, tend not to be as healthy or to live that long.
“This signature of uniqueness can predict patient survival in the last decades of life,” says biochemist Tomasz Wilmanski of the Institute of Systems Biology (ISB).
“Interestingly, this pattern of uniqueness seems to begin in the middle of life – 40-50 years – and is associated with a clear metabolomic signature in the blood, suggesting that these changes in the microbiome cannot simply be diagnoses of healthy aging,” but that they can also contribute directly to health as we age. “
It was remarkable that even as microbiomes diverged in design at older ages, the metabolic functions they performed were consistent between individuals – the researchers found certain longevity-related metabolites in the courage of humans (and various animals) whose microbiomes followed pattern.
As Wilmanski points out, the question remains whether these changes in the composition of microbiomes actually contribute to good health or just reflect it, but it is certainly worthy of further investigation, scientists say – and adds some clarity to a field of research in which the findings were not always clear.
For example, metabolites called indoles have been found to have been linked to reduced inflammation in the intestines of mice – and chronic inflammation is one of the health problems known to increase the risk of mortality in the elderly.
“Previous research on microbiome aging appears to be inconsistent, with some reports indicating a decline in basic gut genes in centuries-old populations, while others show relative microbiome stability to aging-related declines in health,” says the microbiologist. Sean Gibbons, of the ISB.
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 aged 18 to 101, a special cohort of individuals aged 78 to 98 allowed researchers to closely examine how microbiomes and mortality could be linked.
We know that it is at the beginning and end of our lives when our mixture of intestinal bacteria goes through the biggest changes, and this latest study supports the idea that a constantly evolving mixture of bacteria in the stomach is a good sign: it is probably an indicator of a body still flourishing in the last years of life.
The study suggests that a healthy gut microbiome – whatever it may be – may not look the same at different stages of life and is a useful way to explore future research. It seems that our microbiomes can grow in different ways in the elderly, and some of these developments may be healthier than others.
“This is an interesting work that we believe will have major clinical implications for monitoring and altering the health of the intestinal microbiome throughout a person’s life,” says bioengineer Nathan Price of ISB.
The research was published in The Nature of Metabolism.