Why Flatulence Is Simply A Sign Your Bacteria Are Doing Their Job

air-160492_1280Farting. There, I said it.

Here at uBiome we often refer to the microbiome as the bacteria that live in and on your body, but according to a paper co-authored just last month by James Meadow, a former University of Oregon researcher, we really ought to add a third microbial environment to this – the space around the body.

You see, according to Meadow each of us is surrounded by a personal “cloud” of bacteria, at least some of which is generated in the form of flatulence.

And when you fart, your emissions contain a cocktail of different gases accompanied by a liberal side-order of gut bacteria.

Whatʼs more, a good deal of the flatus itself (the scientific word for a fart) is the result of fermentation in your gut, and the work of its bacteria.

The average individual passes wind between 8 and 20 times a day, generating a volume of something like half a liter every 24 hours.

Out of (admittedly rather random) interest it would therefore take about three years for the average person to inflate a camping air mattress with their gastrointestinal gas.

No wonder they sell those little hand pumps.

Although we tend to think of farts as smelly, in fact 99% of their volume is non-odorous, made up of oxygen and nitrogen we swallow, plus carbon dioxide, hydrogen and methane produced by our gut bacteria.

By the way, methane has no odor and, whatʼs more, not everyoneʼs flatus contains it. As a matter of fact itʼs only found in around half the population, so not everybody can pull off the old dorm “fart-lighting” trick.

Even if they wanted to.

The pungent smell of flatus comes from volatile sulfur compounds, including hydrogen sulfide, which make up just 1% of its volume.

Now while you and I probably do our best to avoid other peopleʼs farts, in China there are professional flatus smellers who can allegedly diagnose illness and tell you where it is in the body, simply by taking a sniff.

Actually these experts are not the only ones to actively seek out peopleʼs gas.

According to a recent study at the University of Exeter in the UK, smelling farts could even be good for you.

Apparently a sniff or two of hydrogen sulfide can help to preserve your mitochondria (part of the cell structure of important microorganisms in your body).

Todayʼs brief wander through the world of farts would be incomplete without brief acknowledgement of a phenomenon called High Altitude Flatus Expulsion.


Quite simply, it describes many peopleʼs increased need to pass wind on flights – not because of the airline food – but because of the reduced air pressure outside our bodies.

Thank goodness for efficient aeronautic ventilation, I say.

Finally, it would be remiss of me not to at least tip my hat to a 19th-century entertainer at the Moulin Rouge in Paris who used the stage-name La Pétomane, which loosely translates to “The Fartomaniac”.

Thanks to an extraordinary ability to inhale through his back passage (yup, really) Joseph Pujol (his real name) could produce the sound of cannon fire and thunderstorms from his rear end.

Apparently he also played “O Sole Mio” on an ocarina powered by a rubber tube inserted where the sun donʼt shine, and could blow out a candle from several yards away.

Of course flatulence is the, um, butt of many a good joke.

But the simple truth is that itʼs generally a good indicator of a healthy gut. When your gut bacteria are doing their work, the inevitable side-effect is gastrointestinal gas.

So put that in your ocarina and play it.

Alexandra 🙂

Alexandra Carmichael
Director of Product, Community, and Growth

Further reading

15 Explosive Facts About Farts


Flatulence expert defines ʻnormalʼ output rate

Help Wanted: Professional Fart-Smeller

Humans differ in their personal microbial cloud

Le Pétomane

Study: Smelling farts may be good for your health

Your Body Is Surrounded by Clouds of Skin and Fart Bacteria