Some research studies are funny. Really funny, as in WTF - did they actually do this? I recently read an entertaining article about one such study (done a few years ago) by six physicians who conducted the study on themselves. Each swallowed a small plastic Lego head and then checked their feces (poo!) to see how long it took to be excreted!
They found that the Lego heads actually passed through the gastrointestinal system quite rapidly and without any problems. (But one never found the Lego piece because he didn't thoroughly check!) The researchers (all pediatric health care professionals in either the UK or Australia) had wonderful descriptions of their results - using such terms as Stool Hardness and Transit (SHAT) and the Found and Retrieved Time (FART).
And yes, it actually has real life relevance. The results were reassuring because children swallow small plastic objects all the time, and the study showed they can pass through the system quickly. In this study the average was less than 2 days (1.7 days) for the Lego head to be excreted.
[NOTE: These results do not apply to children swallowing small (button & lithium coin) batteries - that is an emergency situation requiring immediate medical help!]
The writer Sabrina Imbler at the site Defector wrote an entertaining account of the researchers and their study. Excerpt from the article: An Oral History Of The Time Six Doctors Swallowed Lego Heads To See How Long They’d Take To Poo
In 2018, a question burned in the minds of six pediatric healthcare professionals: How long does it take for a small ingested object to pass through a child's digestive system? Unwilling to ask actual children to experimentally swallow a foreign object, these skilled workers volunteered their own gastrointestinal tracts for science, and published a paper detailing their experiment in the Journal of Paediatrics and Child Health, which went viral in a way that papers published in the Journal of Paediatrics and Child Health usually do not.
On that fateful day, on opposite sides of the globe in the United Kingdom and Australia, the six each swallowed a Lego head and waited for the plastic noggins to meander through their large intestines and emerge, triumphant, in a toilet bowl. Five of the pediatricians recovered their Lego heads in a matter of days. One pediatrician never recovered his Lego head. This is their story.
The article even links to a short youtube video showing the beginning of the study (the doctors swallowing the Lego heads)
The original study by Andrew Tagg (and others) in Journal of Paediatrics and Child Health: Everything is awesome: Don't forget the Lego
Aim: Children frequently ingest coins (generally with minimal reported side effects); however, the ingestion of other items has been subject to less academic study. Parental concern regarding ingestion applies across a range of materials. In this study, we aimed to determine typical transit times for another commonly swallowed object: a Lego figurine head.
Methods: Six pediatric health-care professionals were recruited to swallow a Lego head. Previous gastrointestinal surgery, inability to ingest foreign objects and aversion to searching through fecal matter were all exclusion criteria. Pre-ingestion bowel habit was standardised by the Stool Hardness and Transit (SHAT) score. Participants ingested a Lego head, and the time taken for the object to be found in the participants stool was recorded. The primary outcome was the Found and Retrieved Time (FART) score.
Results: The FART score averaged 1.71 days. There was some evidence that females may be more accomplished at searching through their stools than males, but this could not be statistically validated.
Conclusions: A toy object quickly passes through adult subjects with no complications. This will reassure parents, and the authors advocate that no parent should be expected to search through their child's feces to prove object retrieval.