Scientists have discovered a surprising link between bacteria living in the human gut and the rate at which the body ages. Researchers at the University of Hawaii at Mānoa have found that certain gut microbes are associated with slower biological aging, while others are linked to faster aging.
The study, published in Scientific reportsfound that differences in gut bacterial communities accounted for approximately 15% of the variation in participants’ biological aging rates. The findings suggest that the gut microbiome, the vast community of microorganisms living in the digestive system, could provide valuable clues about aging at the molecular level.
“This study advances our understanding of the relationship between the gut microbiome and biological aging,” said lead author Alika K. Maunakea of the UH Mānoa John A. Burns School of Medicine. “We found that microbial patterns in the gut were significantly associated with molecular measures of aging, even independent of chronological age. These results open important new directions for understanding how modifiable biological systems influence long-term health trajectories and longevity.”
Scientists identify gut bacteria linked to faster and slower aging
To study the relationship between gut bacteria and aging, researchers examined stool and blood samples collected from 123 adults of different ages. They identified the bacteria present in each participant’s gut and compared these results with molecular markers in blood used to estimate the body’s rate of aging.
These biological measures differ from chronological age, which simply reflects the number of years a person has been alive. Instead, they are designed to assess how quickly aging-related changes occur in the body.
Researchers discovered a notable association between gut microbiome composition and DunedinPACE, an advanced biomarker that measures the rate of biological aging.
Certain bacterial species stand out for their particularly strong relationships with aging. Bifidobacterium adolescentis was among the microbes most strongly associated with slower biological aging. In contrast, Succinivibrio dextrinosolvens showed one of the strongest associations with faster aging.
These differences suggest that particular profiles of gut bacteria may provide important information about how quickly the body ages.
How diet, lifestyle and environment can influence gut health
Lead author Braden P. Kunihiro said the finding adds to growing evidence that the gut microbiome may play an important role in precision health research, which aims to better understand individual differences in health and disease.
Unlike chronological age, the composition of the gut microbiome can change in response to daily influences including diet, lifestyle, and environmental conditions. This makes it a particularly interesting area of investigation for scientists studying healthy aging.
“The gut microbiome is very sensitive to lifestyle, diet, environment and other daily exposures,” Kunihiro said. “Our findings suggest that the microbiome may reflect important aspects of biological resilience and aging in a way that could potentially help inform future wellness and healthy aging strategies.”
The research also included Native Hawaiian and Pacific Islander participants, groups that have historically received limited representation in studies of aging and gut microorganisms.
Co-author Ruben Juarez explained that including these populations could help scientists study how social circumstances and environmental conditions leave lasting biological effects over a person’s lifetime.
“The microbiome exists at the intersection of behavior, environment and human biology,” Juarez said. “Studies like this help illuminate potential pathways through which lived experiences and social factors influence long-term health outcomes.”
Could the evolution of gut bacteria influence how we age?
Although the results reveal a significant relationship between gut bacteria and biological aging, the researchers emphasize that the study does not establish cause and effect. In other words, the presence of certain microbes in people who age more slowly does not necessarily mean that those bacteria are responsible for slowing down the aging process.
Further studies will be needed to determine whether deliberate modification of the gut microbiome can influence biological aging or improve long-term health.
Still, the findings offer a promising starting point for exploring how the microorganisms living inside us relate to the aging process and whether they could eventually help guide more personalized approaches toward healthy aging.
“This is an important first step toward understanding the relationship between the gut microbiome and healthy aging,” Maunakea said. “Future research will help clarify the mechanisms involved and determine whether these microbial signatures could potentially contribute to precise approaches to promote long-term health and well-being.”
Gn Health
