Body & HealthFact
Your gut isn't a tennis court, but it is a room.
For decades the gut's surface was said to match a tennis court, about 260 square metres. A 2014 measurement put it at roughly 30 to 40 square metres, most of it in the small intestine. The area comes from folds, villi and microvilli that expand the roughly 6-metre tube by a factor of 60 to 120.
Useful: A nice reminder that even textbook numbers deserve a re-measurement now and then.
Source: doi.org