Smart Underwear Reveals We Fart Twice as Much as We Thought

Scientists have created the world’s first wearable device to track flatulence. Their findings? We’re passing gas 32 times a day, not 14 as previously believed.

The Underwear That Counts Your Farts

Scientists at the University of Maryland have created Smart Underwear, the first wearable device designed to measure human flatulence. The tiny device snaps discreetly onto any underwear and uses electrochemical sensors to track intestinal gas production around the clock. Think of it as a fitness tracker for your gut. The device objectively measures human flatulence by tracking hydrogen, revealing that healthy adults produce an average of 32 flatus events per day—about twice previous estimates. Individual variation was extreme, with daily totals ranging from as few as four flatus events to as many as 59.

Why Were We So Wrong About Farting?

Previous research relied on invasive techniques in small studies or self-reporting, which suffers from missed events, imperfect memory, and the impossibility of logging gas while asleep. As gastroenterologist Michael Levitt, known in the field as the “King of Farts,” wrote in 2000: “It is virtually impossible for the physician to objectively document the existence of excessive gas using currently available tests.” The Smart Underwear solves this problem by monitoring continuously, even during sleep when we’re unaware of our gas production.

The Human Flatus Atlas Project

To fill this gap, the Hall Lab is launching the Human Flatus Atlas. The project will use Smart Underwear to objectively measure flatulence patterns, day and night, across hundreds of participants and correlate those patterns with diet and microbiome composition. The HUMAN FLATUS ATLAS is a first-of-its-kind nationwide study using Smart Underwear technology to finally quantify the dynamic range of intestinal gas production and explore what these patterns reveal about gut health and the microbiome. Devices are shipped directly to participants, allowing anyone in the United States to join remotely.

Zen Digesters and Hydrogen Hyperproducers

Hall’s team is recruiting participants across several categories that emerged from their early studies, including Zen Digesters (those with high-fiber diets yet produce minimal flatus) and Hydrogen Hyperproducers (simply put, those who fart a lot). Zen Digesters are people who consume high-fiber diets (25–38 grams of fiber daily) yet experience minimal flatus. These individuals may hold clues to understanding microbiome adaptation to high-fiber diets. If you’re producing 40, 50, or more events per day, your microbiome has a lot to teach us.

Beyond Counting Farts

“We don’t actually know what normal flatus production looks like,” Hall said. “Without that baseline, it’s hard to know when someone’s gas production is truly excessive.” Normal ranges exist for blood glucose, cholesterol, and countless other physiological measures. But for flatulence, no such baseline exists. “The Human Flatus Atlas will establish objective baselines for gut microbial fermentation, which is essential groundwork for evaluating how dietary, probiotic, or prebiotic interventions change microbiome activity.” This research could revolutionize how doctors diagnose and treat digestive issues.