How long we live is influenced by a multitude of factors, with genetics as well as lifestyle playing roles.
It is well established, for example, that what we eat has a direct correlation with our expected lifespan.
Now a study has found that your gut health could determine your likelihood of living to 100.
Researchers from the Novo Nordisk Foundation Centre for Protein Research at the University of Copenhagen studied 176 healthy Japanese centenarians to try to find the answer to a long life.
They discovered that the combination of intestinal bacteria and bacterial viruses in these people was quite unique.
READ MORE: Lung cancer causes to be aware of after Jonnie Irwin terminal diagnosis
First author of the study, Joachim Johansen, said: “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.”
The paper, which was published in Nature Microbiology journal, showed 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,” Simon Rasmussen, one of the study authors explained.
“And seeing as there are hundreds of different types of bacteria in our intestines, there are also lots of bacterial viruses.”
Aside from the important, new, protective bacterial viruses, the team also found that the intestinal flora of the Japanese centenarians is extremely interesting.
Mr Johansen said: “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 ageing related diseases.”
How this could be used in the future
The team designed an algorithm to map the intestinal bacteria and bacterial viruses of the centenarians.
“We want to understand the dynamics of the intestinal flora,” Mr Rasmussen said.
“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.”
This new knowledge on intestinal bacteria could help scientists understand how to optimise the bacteria found in the human body to protect it against disease.
Mr Johansen said: “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.”
Mr Rasmussen added: “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.”