Gut Viruses and Bacteria Linked to Living Past 100
Author: University of Copenhagen - Faculty of Health and Medical Sciences
Published: 31 May 2023 - Updated: 15 Jul 2026
Publication Details: Peer-Reviewed | Research, Study, Analysis
Table of Contents:
Synopsis - Definition - Overview - FAQs - Insights, Updates - Related Content
Synopsis
This research is a peer-reviewed study from the University of Copenhagen, published in Nature Microbiology, that examined the gut microbiomes of 176 healthy Japanese centenarians to understand what sets the very long-lived apart. Using a custom algorithm to map both intestinal bacteria and the viruses that infect them, the team found unusually high microbial diversity along with bacterial viruses carrying extra genes that appear to strengthen beneficial gut microbes, helping stabilize the intestinal flora and counter inflammation. The findings are worth attention for seniors and people with disabilities thinking about long-term health, because unlike our genes, the composition of the gut microbiome can be changed over time, which raises the practical possibility of one day supporting healthier aging by shaping the balance of bacteria and viruses in the intestines.*At a Glance
- 1 - The viruses studied infect bacterial cells rather than human cells, and the gut holds billions of them across hundreds of bacterial types.
- 2 - Certain viruses were found to boost their host bacteria, aiding the transformation of specific molecules in the intestines that may steady the gut flora.
- 3 - Earlier work showed that gut bacteria in older Japanese people produce novel molecules that resist disease-causing microbes, which may help protect against infection and extend life.
Topic Definition
- Gut Virome
The gut virome is the entire community of viruses that live in the human intestines, existing alongside the far more familiar population of gut bacteria. Most of these viruses are bacteriophages, meaning they infect and replicate inside bacterial cells rather than human ones, and because the gut is home to hundreds of bacterial species, it also hosts an enormous variety of these bacterial viruses. Far from being simply harmful, some of them carry genes that can strengthen their host bacteria and influence how molecules are processed in the gut, which affects the stability of the wider microbiome and the level of inflammation in the body. Studying the virome alongside the bacteria gives researchers a fuller picture of the intestinal ecosystem and how its balance may relate to health and longevity.
Overview
"Centenarians Have a Diverse Gut Virome With the Potential to Modulate Metabolism and Promote Healthy Lifespan" - Nature Microbiology.
We are pursuing the dream of eternal life. We fast to stay healthy. And each year, we spend billions of kroner on treatment to make sure we stay alive. But some people turn 100 years old all by themselves. Why is that? Researchers from the Novo Nordisk Foundation Center for Protein Research at the University of Copenhagen have set out to find the answer.
Studying 176 healthy Japanese centenarians, the researchers learned that the combination of intestinal bacteria and bacterial viruses of these people is quite unique.
"We are always eager to find out why some people live extremely long lives. Previous research has shown that the intestinal bacteria of old Japanese citizens produce brand new molecules that make them resistant to pathogenic - that is, disease-promoting - microorganisms. And if their intestines are better protected against infection, well, then that is probably one of the things that cause them to live longer than others," says Postdoc Joachim Johansen, who is first author of the new study.
Among other things, the new study shows that specific viruses in the intestines can have a beneficial effect on the intestinal flora and thus on our health.
"Our intestines contain billions of viruses living of and inside bacteria, and they could not care less about human cells; instead, they infect the bacterial cells. And seeing as there are hundreds of different types of bacteria in our intestines, there are also lots of bacterial viruses," says Associate Professor Simon Rasmussen, last author of the new study.
Joachim Johansen adds that aside from the important, new, protective bacterial viruses, the researchers also found that the intestinal flora of the Japanese centenarians is extremely interesting.
"We found great biological diversity in both bacteria and bacterial viruses in the centenarians. High microbial diversity is usually associated with a healthy gut microbiome. And we expect people with a healthy gut microbiome to be better protected against aging related diseases," says Joachim Johansen.
Once we know what the intestinal flora of centenarians looks like, we can get closer to understanding how we can increase the life expectancy of other people. Using an algorithm designed by the researchers, they managed to map the intestinal bacteria and bacterial viruses of the centenarians.
"We want to understand the dynamics of the intestinal flora. How do the different kinds of bacteria and viruses interact? How can we engineer a microbiome that can help us live healthy, long lives? Are some bacteria better than others? Using the algorithm, we are able to describe the balance between viruses and bacteria," says Simon Rasmussen.
And if the researchers are able to understand the connection between viruses and bacteria in the Japanese centenarians, they may be able to tell what the optimal balance of viruses and bacteria looks like.
Optimising Intestinal Bacteria
More specifically, the new knowledge on intestinal bacteria may help us understand how we should optimise the bacteria found in the human body to protect it against disease.
"We have learned that if a virus pays a bacterium a visit, it may actually strengthen the bacterium. The viruses we found in the healthy Japanese centenarians contained extra genes that could boost the bacteria. We learned that they were able to boost the transformation of specific molecules in the intestines, which might serve to stabilise the intestinal flora and counteract inflammation," says Joachim Johansen.
Simon Rasmussen adds:
"If you discover bacteria and viruses that have a positive effect on the human intestinal flora, the obvious next step is to find out whether only some or all of us have them. If we are able to get these bacteria and their viruses to move in with the people who do not have them, more people could benefit from them."
Even though this requires more research, the new insight is significant, because we are able to modify the intestinal flora.
"Intestinal bacteria are a natural part of the human body and of our natural environment. And the crazy thing is that we can actually change the composition of intestinal bacteria. We cannot change the genes - at least not for a long time to come. If we know why viruses and intestinal bacteria are a good match, it will be a lot easier for us to change something that actually affects our health," says Simon Rasmussen.
Frequently Asked Questions
NOTE: Researched FAQ's by Disabled World (DW)
What is the difference between the gut microbiome and the gut virome?
The gut microbiome is the whole community of microorganisms in the intestines, including bacteria, viruses, and fungi. The gut virome refers specifically to the viruses within that community, most of which infect bacteria rather than human cells.
What is a bacteriophage?
A bacteriophage is a type of virus that infects and replicates inside bacteria rather than human or animal cells. In the gut these viruses are extremely numerous and can influence which bacteria thrive and how they behave.
Can you change your gut microbiome?
Yes, unlike genes, the composition of gut bacteria can shift over time and is influenced by factors such as diet, environment, and health. This ability to change the microbiome is part of why researchers see it as a promising target for supporting long-term health.
Why is microbial diversity considered a sign of gut health?
A more diverse mix of bacteria and viruses generally reflects a resilient gut ecosystem that can better resist disruption and disease-causing microbes. Low diversity, by contrast, is often linked to poorer health and a higher risk of certain conditions.
Why did researchers study Japanese centenarians in particular?
Japan has one of the highest proportions of people living to 100 and beyond, making its centenarians a valuable group for studying the biology of long life. Earlier research had already suggested their gut bacteria produce protective molecules against harmful microbes.
How does gut inflammation relate to aging?
Chronic, low-grade inflammation is associated with many age-related diseases, so factors that help keep it in check are of interest to longevity researchers. The study suggests that certain gut viruses and bacteria may help stabilize the intestinal environment in ways that counter inflammation.
Insights, Analysis, and Developments
Editorial Note: The appeal of this work is that it shifts attention from something we cannot yet control, our genes, to something we already can, the mix of microbes living in the gut. The researchers are candid that practical treatments remain some way off, and their central question is still open: whether the helpful bacteria and viruses found in centenarians could be transplanted into people who lack them so that more of us might benefit. Yet the direction is a hopeful one, framing longevity less as a matter of luck or lifelong fasting and more as an ecosystem that might be tended, with the balance between viruses and their host bacteria emerging as a factor worth understanding before anyone can act on it.*Attribution/Source(s): This peer reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by University of Copenhagen - Faculty of Health and Medical Sciences and published on 31 May 2023, this content may have been edited for style, clarity, or brevity.
* Editorial additions by Ian C. Langtree.