20/01/2016 7:52 PM AEDT | Updated 28/09/2016 9:55 PM AEST

Poop Pills And The Gut Flora With Links To Obesity, Asthma And Our Moods

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Young woman with pill on tongue, close-up

Poo pills are a thing.

Before you turn your nose up, consider this: the scientific world has long had a gut feeling that the microorganisms living inside us can influence our moods and contribute to illnesses like arthritis and asthma.

And the studies are backing it up.

Last year, an Australian experiment showed a transplant of healthy poo could cure a mouse infected with two antibiotic-resistant superbugs.

New research by the University of NSW this week showed the gut bacteria of mice could be decimated by the odd junk food binge. The study also showed the make-up of organisms in healthy mice was very different to unhealthy, or yo-yo dieting mice.

Yet another study in 2013 showed bacteria linked to slim mice.

Many of these studies involve mice because the field is still in its infancy. As University of Queensland Centre for Superbug Solutions director Matt Cooper said, we are only just really starting to understand the effect of our gut on our mind.

"You know how your grandma used to say you are what you eat? Well she’s a smart lady," Cooper said.

"What we’re understanding now is it’s not just about digestion and gut health and obviously obesity -- it’s interrelated with a whole bunch of diseases.

"Our diet really influences our microbial composition and we’re understanding now how that happens. We didn’t have the tools to do that until about 10 years ago."

He said there was a causal link between gut bacteria and all sorts of processes in the body, partly through a type of short-chain fatty acid created by bacteria that loves a high fibre diet.

"Receptors in the gut pick up these short-chain fatty acids from the good bacteria and they translate it into signals to the brain and the liver in terms of energy and metabolism, so they can tell the brain to make insulin or not," Cooper said.

"They can tell the liver whether or not to activate pathways that can then regulate energy uptake.

"Theres a clear link between a high-fibre diet, healthy bacteria, short-chain fatty acids and how we regulate energy and metabolism in the body."

Which brings us to the discovery of poo transplants. Cooper said the technique could potentially undo the damage of smoking -- again, in mice.

He said a mouse exposed to smoke had a greatly reduced amount of microorganisms associated with asthma.

"When you transfer poo from a normal mouse into a smoking mouse you can take the asthma away," Cooper said.

So if you don't like the idea of bacteria living inside you, think of it the way Cooper does.

"You could say that we are hosting a colony and environment and community of bacteria that are actually using us to get around," Cooper said.