In an episode of Today I Found Out, Simon Whistler explains the reasons why other people’s farts smell worse, and why people can’t tickle themselves. The two seemingly unrelated situations are surprisingly connected thanks to how the brain processes sensory information.
In 2005, two researchers published a series of articles investigating the subject of other people’s smelliness. They examined how much disgust people would feel and show after smelling a variety of odors, including armpits, garbage and farts. Among the stinks examined, farts elicited the strongest negative response, and across all body odors, people consistently rated odors of other people worse than their own (with one notable exception in that the armpit sweat of one’s partner was generally rated as less offensive than a person’s own.