We now know why some poos float and others sink

The person is Alice Klein.

The types ofbacteria in your gut and how much gas they produce can affect whether your poo floats or sinks.

Some people do poos that float in the water, while others do poos that sink to the bottom.

It was shown in 1972 that the gas content of faeces was the main reason for this. Even if they had high fat content, the floaters sank when the gas inside was removed by pressurisation.

The research was prompted by the revelation that his poos were always floating. After our discussion, he passed a stool, we put it in a flask, pressurized the flask, and watched the stool sink to see if it floated because of its gas content.

Two floaters they tested contained high levels of methane gas, which is made bybacteria that ferment sugars as they pass through the large intestine. They couldn't say for sure.

Nagarajan Kannan and his colleagues have confirmed that germ-free mice are more likely to produce floaters than standard mice.

The researchers injected gutbacteria collected from the faeces of standard mice and from two seemingly healthy young women into the stomachs of germ-free mice and found that it caused many of their poos to start floating.

There is no confusion as to what makes stool float, it is gas from the gut. A closer analysis of the mouse floaters showed they contained multiple gas- producingbacteria, including Bacteroides ovatus and Bacteroides uniformis, which are known to increase methane production and the occurrence of flatulence in people.

Kannan says that the next step will be to individually introduce each of them into the guts of germ-free mice. He says that microbial analysis of human faeces could show which gas- producingbacteria are more common in floaters.

Read more: Faecal transplants ease irritable bowel syndrome for three years

Kannan says that the mix ofbacteria found in the gut can be influenced by a number of factors, including diet, genetics, delivery at birth and environment.

We don't know if it is better to do floaters or sinkers at this point. It's possible that it depends on which gutbacteria are making the gas.

The scientific reports is a journal.

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