As weird as it sounds, scientists think vital clues to longevity might be lurking in people's poo. Especially really fit and really old people's poo.
According to University of NSW gastroenterological specialist Professor Emad El-Omar, human faeces - like that of all animals - is a microbial and biochemical goldmine.
Much can be gleaned about disease and ill-health, for example, during a close-up look at the waste matter of someone who is already sick, he says.
But until now, researchers have thought relatively little about what constitutes a normal "home state" for gut microbes.
The Healthy Optimal Australian Microbiome or HOAM Study will aim to fill that gap, Prof El-Omar said, by defining what a healthy microbiome looks like.
The DNA of all the microbial communities that live in and on the body differs considerably in type and proportion from person to person.
However if his team can determine what normal is and is not, it should be able to design interventions to restore normality to the microbiota with a view to improving health and limiting the effects of ageing, Prof El-Omar said.
"Getting to extremely old age while still being cognitively well is a tremendous achievement," he said.
"We are hoping there is something in the microbiome of healthy centenarians that can tell us how to age well.
"By studying what the microbiome looks like in healthy and cognitively robust older adults we can determine the factors that have helped them to age so well."
But it is not just centenarians the researchers are hoping to recruit.
The study is a multi-generational one, looking at the microbiome across the lifespan from 13 years of age to 95 and older.
It is also non-interventional, so there are no medications to take or treatments to undergo.
Participants simply provide stool and blood samples along with an oral swab, and complete some clinical assessments.
Initially the researchers are hoping to hear from cognitively well and healthy adults 65 and over, and healthy athletes 18 and over who exercise more than three hours a week.
"Healthy and supremely fit athletes also offer a unique insight," Prof El-Omar said.
"Not only are they physically fit but they must be at the top of their game emotionally and mentally.
"We want to see what in their microbiome might help them achieve peak physical, metabolic, cardiovascular and mental performance.
"We are trying to define the microbiome of optimally healthy individuals across the age spectrum."
Australian Associated Press
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