How often does the average person fart? Scientists built a device to find out

‘Smart underwear’ could help unlock the secrets of human flatulence

By Claire Cameron edited by Tanya Lewis

Whether you’re knocking out wind, farting loudly, or letting out a little cry, flatulence is, whether you want to admit it or not, a daily necessity just like breathing. But exactly how often the average person gets ripped and what that says about their body remains a mystery.

“We don’t really know what normal flatulence production looks like,” Brantley Hall, an assistant professor at the University of Maryland, said in a statement. (Flatus is the technical term for a fart.) “Without this baseline, it’s difficult to know when a person’s gas production is truly excessive,” he added.

Smart Underwear, a wearable device co-created by Hall and colleagues, could help answer this crucial question. (Hall has applied for patents related to the technology and is co-founder of a company that has licensed it.)

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The wearable isn’t really underwear, but rather a device that attaches to clothing and uses chemical sensors to track intestinal gases, particularly hydrogen, produced by microorganisms in the gut. Typically, farts are a mixture of microbially produced hydrogen and sometimes methane, as well as carbon dioxide and oxygen produced by the body.

In a study of the device, Hall and his team found that healthy adults farted about 32 times a day, although some only farted four times, while others farted 59 times a day. The study, however, did not measure whether the farts were smelly or audible.

Hall and his team tested the device on 19 healthy adults, all of whom wore it in their underwear for a week while they were awake, except when doing strenuous exercise or traveling. In another experiment, 38 participants wearing the device followed a special low-fiber diet for four days. On the fourth day, the researchers gave these participants fiber supplements, which caused them to produce more hydrogen gas, to see if the smart underwear could make a difference. As hoped, Smart Underwear detected increased microbiome activity in the presence of fibers, according to an article describing the study, published in Biosensors and bioelectronics:.

The range of daily fart frequencies challenges “the assumption that a median amount of flatulence per day can adequately describe human physiology,” Hall and co-authors write in the paper. Knowing how much the average person farts can help inform treatments for people with excessive flatulence or other problems.

Smart Underwear is just the first step. Hall also launched the Human Flatus Atlas to recruit and measure flatulence in the population. Researchers are particularly interested in studying people who eat a high-fiber diet but don’t fart a lot and people who fart. a lot.

“We have learned a tremendous amount about the microbes that live in the gut, but less about what they actually do at any given time,” Hall said in the release. The Human Flatulence Atlas could help establish a population-wide baseline for flatulence. And that, in turn, could help researchers develop better treatments for gut health.

Editor’s note (02/12/26): This article was edited after publication to correct the description of the study experiments.

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