Short Wave - Farts To The Rescue

Episode Date: January 29, 2025

Farts are funny and sometimes smelly. But are they a legitimate topic of research? More than 40% of people worldwide are estimated to suffer from some kind of functional gut disorder — from acid reflux, heartburn, indigestion, constipation and irritable bowel syndrome to inflammatory bowel disease. So, yes, freelance science writer Claire Ainsworth thinks so. Claire speaks with Emily about two teams of scientists studying intestinal gases, who she profiled in a recent New Scientist article — and why understanding people's gut microbiome through a fart-shaped window may help treat these conditions at the source. Read more of Claire's reporting for New Scientist.Have another bodily function you want us to explore or just want to report to us about a funny time you passed gas? Email us at [e-mail] to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave.See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

Hi, Shortwavers. Have you ever wanted to ask a marine biologist, I don't know, anything, like about sea stars or sponges or other ancient spineless creatures of the ocean? Maybe you've wondered what it's like to live underwater or how you even become a marine biologist. Well, we're talking to one soon and we want to ask them your questions. Send them in by recording your name, location, and your question in a quiet space and email that audio to Shortwave at npr.org. by the end of the day on Thursday, January 30th. Yes, I'm giving you a deadline. Thank you so much and enjoy the show. You're listening to Shortwave from NPR. Farts are funny.

Depending on where you are and who you are, they might also be smelly or silly or just rude. But could they be a topic of scientific research? There are some scientists who are trying to collect them, physically collect farts. Claire Ainsworth got her PhD in developmental biology, and she's now a freelance science journalist based in the UK who covers things like farts. I thought, what on earth is motivating these people to go to such lengths and such care to collect farts? You know, how do they a funding for that? Why would you do that?

And it took me on this, this is a really fascinating journey into just how important and fascinating farts really are. Claire published a piece about all she'd learned in new scientists, which is a science magazine, in December. She says, think of farts like a window into the giant microbial world that lives inside of us in the largest microbiome in the human body, our gut. Microbes along the GI tract break down what we eat, aiding with nutrient absorption, regulating our immune systems, and yes, producing intestinal gases. But studying people's gut microbiome directly and non-invasively is difficult. Like beyond sampling what comes out either end of the human body, how do you learn what's inside? And this is why gases are so cool because they kind of let us eavesdrop on the conversations that are going on within this ecosystem and how that relates to our health. And to our diet, more than 40% of people worldwide are estimated to suffer from some kind of functional gut disorder.

These are chronic conditions like acid reflux, heartburn, indigestion, constipation, irritable bowel syndrome, inflammatory bowel disease. They can be really painful, so understanding our gut microbiome through a fart-shaped window may help treat these conditions at the source. If only, Claire says, we could study the gases themselves as they billow and bulge through our digestive system. You know, most of the gut is this big black box. What we really would like to do is look at what's going on in real time. and how it responds to changes in diet. So today on the show, Farts to the Rescue, how gases move through our gut.

And two experimental methods, scientists are testing out to catch gas to better care for the gut microbiome. I'm Emily Kwong, and you're listening to Shortwave, the science podcast from NPR. Farts are made in our gut, and our gut is long, at least 15 feet. It's a twisting,

landscape through which our intestinal gases move. Some of the gas that comes in is you swallow it. Your mom probably told you off from eating too fast. You swallow gases like oxygen and nitrogen. Most of that comes from swallowed air. Those gases travel down to your stomach through your intestines, down to your colon. And all along the way, your gut microbes are fermenting the food you eat

and producing more gases, carbon dioxide, sulfur. Some even eat those gases and release others. And this is the cocktail that comes out the other end. You know, you feed yourself, but you also feed your gut bacteria, your gut microbes with your diet. And it's this fermentation, then producing these gases. But before the gases come out, which is the exciting and embarrassing part, I wanted to ask Claire, what happens along the way? Like, how are the gases interacting with, say, ourselves? Yeah, so these are the things like hydrogen sulfine or methane.

they are gases that can act as signals. They tell ourselves to do things. They can affect how our immune cells respond. They can affect the blood vessels in the gut. They can affect the function of the gut and affect other parts of our bodies as well. They could promote gut and liver health, for example, that sort of thing. So they're not just waste effluent. They're not thinking like a factory chimney set, the belt does out smoke.

They have a function. So what's the end product? Like, how is the fart different from the gases that are, like, in the tube before it comes out? Well, I guess it's much more complicated than what goes in at the top. Yeah. In many ways, you kind of fart when we breathe as well, because I've only just met you know, insulting. I do apologize. The problem, of course, with measuring breath is it doesn't tell you where the gas is being produced, which bit of the gut.

And that's key, really. Right. Herps are not as illuminating in this regard as farts are. You know, when you say come out at the other end, it's composed of gases, you know, like carbon dioxide, depending on what else you've been eating hydrogen, methane, perhaps, that sort of thing. But also a whole load of other stuff, these tiny trace amounts of things like hydrogen sulfide, these volatile organic compounds I mentioned, that probably lend a certain bouquet to the whole proceedings. the smell, should we put it.

Right. So, yeah, so what actually comes out, farts are actually really complex. They're very dynamic. And they, like I said, they give us a rather, you know, slightly smelly window into what's been going on on our insides, at least towards the end of our gut. Okay, so in reporting this story, you started looking around for different methodologies to measure this slightly smelly window. Yes.

You found two very promising ones. We're going to talk about both. The first was developed by a team in Spain at the University of Barcelona. Tell me about that. What are they doing over there to try to catch farts? Okay, so the Spanish team was led by Santiago Marco

at the Institute of Bioengineering of Catalonia and Antonio Pardo at the University of Barcelona. Okay. And one of them, the ways they've been trying to do, trying is a not to put, to find a point of it, a catheter up the rectum. Ah. So a tube. Up the butt.

To gather the fart. To gather the gas. One of the problems with this is, A, it's a little bit invasive, but also you can contaminate a sample with atmospheric air. It can leak in. Yep. And also there's, how do you measure it? How do you measure it accurately?

How do you get, you know, reproducible findings from it? So this was the challenge, this team took on. So they designed a fart. catching device, which is a tube up the rectum with a special plug in it to keep the atmospheric gas out and a special bag for collecting gas. And then they've got five volunteers, set them up and said, don't move. Stay very still for the next four hours and we'll collect some gas. Wait, so the volunteers sat there, were they encouraged to fart? If you've got a tube up there, I don't think, I don't know how much volunteers you

control you have over it, to be honest. Yeah. It's just kind of whatever came out was gathered. Yeah. Okay. Got it. Got it. And they then, they took them over to the scientists who used the technique called

gas chromatography on the parts. And this is a very sensitive, very precise way of measuring what molecules are in a sample, right? What did they find? Well, they found, actually, they could detect with, you know, good accuracy, the five main gases in farts, so oxygen, nitrogen, carbon dioxide, methane. And they gave the subjects a meal that either didn't make the fart much or was predicted to make the fart a lot. And then did the experiment again. And then they were able to show in their gas chromatography measurements, they could tell the

difference between the samples. Right. They fed some volunteers a high flatulence diet of bananas and white beans and other volunteers a low flagellins diet of orange juice and a sandwich and they could tell like through the gas sample the difference which is a big deal it's a promising procedure for intestinal gas research yeah but um the idea was that actually you can use this to get a really nice accurate reproducible way of detecting what's those gases um in farts yeah yeah and the second potential method for getting fart data comes from a medical device company in Australia called Atmo Biosciences, and they invented an actual capsule. So something people swallow that can sniff out intestinal gases along the gut and then like transmit data to be analyzed. How does that all work?

Yeah, so this is the Atmo capsule, and it builds on work from a number of scientific groups around the world. And obviously we can't swallow a gas chromatograph, but we can send something else in that doesn't have that same sort of analytical power, but still, you know, as a trade-off, tells us stuff we couldn't find out any other way. It's like when the magic school bus gets swallowed by Arnold and they like learn all about his different systems. Yeah, it's kind of like that. Yeah, a little bit like that. So they've got this little capsule and it's about half the size of a sort of AA battery and you can swallow it. It's like a big pill. And it makes its way through your gut over a couple of days and it can detect hydrogen carbon dioxide and it can also work out

through various means if there's a low oxygen in the area and it's got a temperature sensor so it knows when it's come out the other end you know atmo has left the building and the great thing about it is it transmits its results telemetrically to a receiver outside the body you just send the data off for analysis one of the useful things it can tell you is whether fermentation is taking place at a particular point in the gut. So the cool thing is you know where it is, and you know, for example, if there's hydrogen there, if there's hydrogen there, there's got to be fermentation.

It can tell you where in your gut gases are coming from? Yeah. Wow. And one of the theories in IBS is that it's the location of fermentation that might be an issue. And they showed, for example, that by changing diet, and measuring it with these capsules, they were able to show that change in the diet shifted the location of fermentation in the colon.

Yeah. And it's important to say, of course, this capsule is not available for sale. It's not on the market. It needs to go through a lot more regulatory approval and experimentation. But taking a step back, you know, when you think about all the reporting you did for this story and all the scientists you've talked to, Has this been helpful for you and your farts?

And do you have any advice for people currently suffering from a functional gut disorder of some kind? I almost say it gives me a whole new appreciation of farts. It's a classic Cinderella story, isn't it? It's rags to the riches. We thought they were rubbish. We tried to get rid of them or hide them. But you know, you can take pride in your farts. They are a miracle of biology.

But maybe keep that miracle to yourself in the bathroom. for now. That's right. Farts are hilarious, right? I mean, I had a lot of fun reporting this story, but there's a very serious side to it because, you know, these gases can help us understand some diseases that cause a huge amount of suffering worldwide. You know, if you're affected by any of these issues, what I suggest is to seek out good quality information. You know, don't try and treat yourself with a diet because there's so much rubbish. You know, try this bad diet or buy that overpriced supplement to fix your problem. what you want is good evidence-led treatment from a physician.

It's very early days, but people are working on it. Claire Inesworth, thank you so much for talking to me about this work. I don't problem. And before we go, we want to say a big thank you. If you are one of the listeners who answered the call in the last few months and supported our show by signing up for NPR Plus, Oh my gosh, that support is so important to keep our work going. Thank you. Thank you.

And if you have heard about NPR Plus but aren't supporting us yet, it's so easy to sign up. Just go to plus.npr.org. This episode was produced by Hannah Chin. It was edited by our showrunner, Rebecca Ramirez, and fact check by Tyler Jones. Quasi Lee was the audio engineer. Beth Donovan is our senior director and Colin Campbell is our senior vice president of podcasting strategy. I'm Emily Kwong. Thanks, as always, for listening to Shortwave, the science podcast from NPR. I'm not very good at doing fart noises. I didn't get that particular elementary school training.

I can't believe this is my job.