Of course, everyone passes gas, and most of us accept that a little smell is just part of being human. Still, the research from 1998 suggested that women’s farts carried a sharper scent for a surprisingly simple reason.
The study has continued to spark curiosity because of how direct and unusual the findings were.
To understand how the study operated, he recruited 16 healthy volunteers who had no known digestive issues. Each participant wore a “flatus collection system,” which was essentially a rectal tube connected to a sealed collection bag.
This setup allowed researchers to gather samples safely and consistently without relying on random timing.
Once collected, the samples were analyzed using a gas chromatographic–mass spectroscopic test, which helped the researchers break down exactly what chemicals were present in each bag.
This gave the team a clearer view of the gases responsible for the strongest smells.
The judges, unaware that they were actually smelling human farts, scored the odors on a scale from 0 to 8, with 8 meaning “very offensive.”
Their ratings helped confirm the scientific findings that sulfur-containing gases—especially hydrogen sulfide—were the main drivers of strong-smelling flatulence.
The Cleveland Clinic has further explained the science behind flatulence. Gastroenterologist Christine Lee shared that gas forms in two main ways: through digestion and through swallowing air.
Both processes contribute to the composition and smell of a person’s farts.
She also explained that the average person swallows about two quarts of air every day while eating, talking, drinking and even snoring. Some of this air returns as burps, but the rest may move through the digestive system before being released as gas.
The more you know.
