How was Stonehenge built? What are the main statues on Easter Island? Why do some poos float, while others sink to the bottom of the bowl?
These are just some of the big questions we face in life.
It’s one of the many mysteries of toilet time, and admittedly it’s kept us up at night.
Well, now researchers have taken another look at an old study, which seems to offer some insight.
According to research from the University of Minnesota Hospitals, whether poop is a “floater” or a “swimmer” depends on the types of bacteria in your gut and how much gas they produce.
Published in 1972, the study examined waste from 13 people and found that they all sank when the gas inside was removed by increased pressure, even though they were high in fat.
At the time, gastroenterologist Michael Levitt and his student William Duane were inspired to look into the subject when Mr Duane’s poos always flowed.
“About two hours into our discussion, he passed a stool, we put it in a flask, and pressurized the flask and watched the stool sink, demonstrating that the stool floated because of the gas content,” Levitt said.
They thought this gas came from intestinal bacteria being incorporated into the stool, but they were never able to confirm their suspicions.
Now Dr Nagarajan Kannan at the Mayo Clinic in Minnesota and his colleagues have confirmed this hunch, New Scientist reported.
They noticed that mice bred to have no gut bacteria — known as germ-free mice — always produce sinkers, while nearly half of standard mice produce floaters.
“Now there is no confusion as to what causes the stool to flow, it is gas from gut microbes, not from swallowed air or other sources,” said Dr Kannan.
“Closer analysis of the mouse whistles showed that they contained several gas-producing bacteria, including Bacteroides ovatus and Bacteroides uniformis, which are known to increase methane production and the frequency of flatulence in humans.”
But his team is still a long way from establishing that floaters or sinkers indicate better gut health.
“It probably depends on exactly which gut bacteria are producing the gas,” he said.
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