Researchers are testing "smart underwear" sensors that track when people pass gas—while also recording diet and daily habits.
Early results show people average about 32 gas events per day, though the range varies widely.
The goal is to better understand the gut microbiome and what actually counts as normal digestion.
Everyone does it. Whether you call it breaking wind, passing gas, or cutting the cheese, flatulence is a normal part of digestion.
However, here’s something scientists still don’t fully understand: how much gas is actually normal?
Researchers at the University of Maryland are now trying to answer that question with a nationwide study that uses what they call "smart underwear."
How the smart underwear works
The study uses a small wearable sensor that clips onto participants’ underwear.
The quarter-sized device measures intestinal gas using electrochemical sensors that detect when gas is released.
Participants also track:
- What they eat
- Their daily habits
- Demographic information
Researchers hope the data will help identify why some people pass gas far more often than others.
A window into the gut microbiome
The study might sound like bathroom humor, but the science behind it is actually serious. Researchers are trying to better understand how the gut microbiome works.
Your digestive system is home to trillions of bacteria that help break down the food you eat. When those microbes digest things like fiber and certain carbohydrates, they naturally create gases such as hydrogen, methane, and carbon dioxide.
By tracking how often gas is released and comparing that with people’s diets and daily habits, scientists hope to uncover new clues about:
- Digestive health
- Food tolerance
- Gut bacteria behavior
- Early signs of gastrointestinal disorders
Scientists say the findings could eventually help doctors give patients more personalized dietary advice and identify digestive problems earlier.
Researchers expect early findings from the larger study within about a year.
Early results already surprised scientists
In a small early study of 19 adults, the sensor tracked how often people passed gas in a typical day.
The result: about 32 times per day on average.
This is more than double the number often cited in medical literature.
However, the range was enormous. In one example, two participants with nearly identical diets passed gas 175 times and 5 times in the same day.
Thousands of people have volunteered
The new nationwide project, called the Human Flatus Atlas study, originally aimed to enroll 800 participants. Instead, more than 3,000 people across the U.S. have already signed up.
If interested, you can join the study as well. You'll be asked for your name, email address, and a few questions to determine your eligibility.
According to the research team, participants have been surprisingly open about sharing stories about digestive issues and embarrassing moments caused by excessive gas.
Researchers say the interest likely comes from a simple question many people have asked themselves at some point: “Is this normal?”
One thing scientists already know
One thing scientists already know is gas varies wildly from person to person.
So, if you’ve ever wondered whether you’re “normal” when it comes to flatulence, you’re definitely not alone. Researchers say thousands of Americans are curious about the exact same thing.