With ingestible pill, you can track fart development in real time on your phone

Scientists often hope to break ground with their research. But a group of Australian researchers would likely be happy with breaking wind.

The team developed an ingestible electronic capsule to monitor gas levels in the human gut. When it’s paired with a pocket-sized receiver and a mobile phone app, the pill reports tail-wind conditions in real time as it passes from the stomach to the colon. The researchers, led by Kourosh Kalantar-Zadeh of RMIT University and Peter Gibson of Monash University, reported their invention Monday in Nature Electronics.

The authors are optimistic that the capsule’s gas readings can help clear the air over the inner workings of our intricate innards and the multitudes of microbes they contain. Such fume data could clarify the conditions of each section of the gut, what microbes are up to, and which foods may cause problems in the system. Until now, collecting such data has been a challenge. Methods to bottle it involved cumbersome and invasive tubing and inconvenient whole-body calorimetry. Popping the electronic pill is a breeze in comparison. And early human trials have already hinted that the pill can provide new information about intestinal wind patterns and gaseous turbulence from different foods.

“Our pilot trial illustrated the significant potential role for electronic-based gas-sensing capsules in understanding functional aspects of the intestine and its microbiota in health and in response to dietary changes,” the researchers concluded.

The authors are currently setting up a commercial company to further develop and test the capsules.

Toot tracker

For their pilot study, the researchers beefed up a prototype they had previously tested in pigs. The capsule is 26mm in length, with a 9.8mm external diameter—like a large vitamin. Its polymer shell surrounds sensors for temperature, CO₂, H₂, and O₂, as well as a button-size silver oxide battery and a transmission system. One end of the capsule contains a gas-permeable membrane that allows for fast diffusion of gut gases.

In the trial published Monday, researchers tested the capsule in six healthy people. For the first, researchers monitored the pill’s intestinal trek using ultrasound and linked locations with gas profiles. Overall, it took 20 hours to get from one end to the other, spending 4.5 hours in the stomach, 2.5 hours in the small intestine, and 13 hours cruising through the colon.

In that time, the pill took continuous gas measurements, revealing potentially useful information in addition to gut position. For instance, CO₂ and H₂ levels peaked in the early hours of its time in the colon while O₂ levels crashed throughout this stretch of the trip. That jibes with the horde of anaerobic bacteria (those that live without oxygen) that inhabit the colon. There, they ferment undigested food bits into short-chain fatty acids that play significant roles in our health and metabolism.

Gusty guts

In the next human trial, the researchers had one person gulp the pill twice. The first time, he ate a very high-fiber diet (50 grams per day) for two days prior to swallowing the pill. Two weeks later, he gulped another pill after eating a low-fiber diet (15 grams per day) for two days.

In the high-fiber test, the man passed the pill in about 23 hours. But he was not happy about it. The super dose of fiber caused abdominal pain. In its four hours in the colon, the pill recorded elevated levels of O₂, which could mess up anaerobes. Indeed, an analysis of fecal bacteria during this phase showed a shift toward species associated with poor gut health.

There were also problems in the low-fiber scenario. The pill took a little more than three days to work its way out. It spent 13 hours in the stomach, 5.5 in the small intestines, and a whopping 54 in the colon. In fact, about 36 hours after taking the pill, the man was given a high dose of fiber to try to move things along. Prior to that fiber intervention, H₂ gas levels in the colon had plummeted, suggesting a drop off in fermentation. It picked back up 12 hours after the fiber treatment, the pill data showed.

Last, the researchers recruited four more healthy patients to pass the pill. Two ate a high-fiber diet (though not quite as high as the last trial), while the remaining two ate a low-fiber diet. Gases billowed in their bowels with similar patterns seen in the earlier trials.

In an accompanying editorial, mechanical engineer Benjamin Terry of the University of Nebraska-Lincoln concluded that the capsules “have remarkable potential to help us understand the functional aspects of the gut microbiome, its response to dietary changes, and its impact on health.”

“It might not be too long before a routine healthcare visit involves a check of your vital signs and a request to swallow a tiny electronic monitoring device,” he added.

Nature Electronics, 2018. DOI: 10.1038/s41928-017-0004-x  (About DOIs).