Help us: Donate
Follow us on:

Male and Female Gut Microbiomes Converge With Age

The exact reason for this change is unknown but is linked to physiological aging.

Male and female intestinesMale and female intestines

While the gut microbiomes of young men and women are distinct, that difference disappears in older people, according to a new study. These findings add to the growing pool of data that links the gut microbiome and aging, although the nature of the links and the mechanisms behind them remain questions for future research.

The gut microbiome has been linked with many aspects of our biology, from immune response regulation to involvement in disorders such as diabetes. Studies in a variety of animals have reported sex-linked differences in the gut microbiome, but the findings have been somewhat inconsistent, perhaps because of the influence of other factors, such as diet and environment. These inconsistencies led a team of researchers at Chinese institutes to investigate how the gut microbiomes of a population in Beijing varied with sex, sex hormones, age, and a range of metabolic and clinical metrics.

The researchers sequenced the microbiomes of 2,338 adults aged 26-76 in Beijing and correlated this data with 88 parameters measured through lab tests and questionnaires. They found that it was possible to distinguish the gut microbiomes of men and women aged 26-50, but in individuals older than 50, this difference disappeared. The researchers were able to validate these findings in an independent cohort from China and another from the Netherlands, but not in an Israeli cohort.

The age-related changes in the microbiome didn’t correlate with sex, diet, or the lifestyle or metabolic parameters measured in the study. In other words, it seems that the microbiome probably changes as a result of age-related physiological changes rather than alterations of diet or lifestyle. Characterizing these changes and understanding how they work could offer insights into what happens during aging or at least tools to probe this particular aspect further.

The team tried to use their findings to establish a “microbiome clock” – an estimator of age based on microbiome data – but they found that it performed well in some cohorts but poorly in others.

Unlike Horvath’s methylation clock that accurately reflects the rate of host intrinsic aging at the molecular level, the gut microbiota-based age-prediction models based on a combined set of age-associated microbial features at both the individual and population levels seem to be less universally applicable.


Lifelong sex- and age-related trajectories of the human gut microbiota remain largely unexplored. Using metagenomics, we derived the gut microbial composition of 2,338 adults (26–76 years) from a Han Chinese population-based cohort where metabolic health, hormone levels and aspects of their lifestyles were also recorded. In this cohort, and in three independent cohorts distributed across China, Israel and the Netherlands, we observed sex differences in the gut microbial composition and a shared age-related decrease in sex-dependent differences in gut microbiota. Compared to men, the gut microbiota of premenopausal women exhibited higher microbial diversity and higher abundances of multiple species known to have beneficial effects on host metabolism. We also found consistent sex-independent, age-related gut microbial characteristics across all populations, with the presence of members of the oral microbiota being the strongest indicator of older chronological age. Our findings highlight the existence of sex- and age-related trajectories in the human gut microbiota that are shared between populations of different ethnicities and emphasize the pivotal links between sex hormones, gut microbiota and host metabolism.


This isn’t the first study to investigate the link between the gut microbiome and aging, and it almost certainly won’t be the last. This study represents an extensive analysis of a well-defined cohort, together with validation in other cohorts, resulting in a wealth of data about the trajectory of the gut microbiome. The paper also digs into the effect of sex hormones: testosterone is associated with microbiome diversity, while estrogen isn’t linked, but this doesn’t seem to be connected with the difference between sexes. It’s not clear if or how changes in sex hormones are linked with the disappearance of distinct sex-based microbiomes with age. The complex interplay between sex hormones, age-related physiology, the gut microbiome, and other aspects of aging will doubtless provide fodder for years of research.

We would like to ask you a small favor. We are a non-profit foundation, and unlike some other organizations, we have no shareholders and no products to sell you. We are committed to responsible journalism, free from commercial or political influence, that allows you to make informed decisions about your future health.

All our news and educational content is free for everyone to read, but it does mean that we rely on the help of people like you. Every contribution, no matter if it’s big or small, supports independent journalism and sustains our future. You can support us by making a donation or in other ways at no cost to you.

Long-Term Resistance Exercise Increases Autophagy

In a new systemic review published in Autophagy Reports, researchers have demonstrated that exercise plays a role in regulating autophagy,...

A Lasting Rise in Investment in the Longevity Sector

2021 marked one of the biggest years in longevity financing, with 2022 following closely behind, according to a report by...

Mediterranean Diet Might Lower Risk of Dementia

In a large-scale observational study, British scientists have shown that high levels of adherence to the Mediterranean diet might substantially...

Lifespan News – Protein and Muscle

Emmett Short brings up a study talking about how diets with less protein are connected to better muscle maintenance with...


[1] Zhang X, Zhong H, Li Y, Shi Z, Ren H, Zhang Z, Zhou X, Tang S, Han X, Lin Y, Yang F, Wang D, Fang C, Fu Z, Wang L, Zhu S, Hou Y, Xu X, Yang H, Wang J, Kristiansen K, Li J, and Ji L. Sex- and age-related trajectories of the adult human gut microbiota shared across populations of different ethnicities. Nature Aging (2021), doi: 10.1038/s43587-020-00014-2

[2] Özkurt E and Hildebrand F. Lifelong sex-dependent trajectories of the human gut microbiota. Nature Aging (2021), doi: 10.1038/s43587-020-00019-x

About the author
Sedeer el-Showk

Sedeer el-Showk

Sedeer became a professional science writer after finishing a degree in biology. He also writes poetry and sff, and somehow juggles an ever-growing list of hobbies from programming to knitting to gardening. Eternal curiosity and good fortune have taken him to many parts of the world, but he’s settled in Helsinki, Finland for the moment. He hopes he’ll never stop learning new things.
No Comments
Write a comment:


Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.