Parents go to great lengths to make sure their toddlers don’t swallow coins, batteries, toy pieces, pebbles, bugs and other chokable items that litter a child’s world. But, inevitably, kids swallow things. That’s why a group of healthcare professionals decided to find out just how long a Lego stayed in the human body by experimenting on themselves.

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Amanda Kooser at CNET reports that doctors associated with the medical blog Don’t Forget the Bubbles knew that there was a lot of data about swallowing coins, the foreign object most commonly swallowed by children, which take about 2 weeks to pass. But data on how long it takes a plastic toy piece to worm its way through the body is scanty. That’s why they recruited test subjects with no history of intestinal surgery to swallow the plastic head of a Lego figurine. They then examined their poo to see how long it took until the decapitated Lego head came out.

Bruce Y. Lee at Forbes reports that each participant kept a 3-day stool log, rating their bowel movements using a Stool Hardness and Transit (SHAT) score. A person with higher SHAT score had looser and more frequent bowel movements, meaning the smiling little piece of plastic may move through more quickly.

After swallowing the Lego noggin, each participant was responsible for analyzing their own poo to locate the object. According to the blog, “[a] variety of techniques were tried – using a bag and squashing, tongue depressors and gloves, chopsticks – no turd was left unturned.”

After retrieving the Lego head, the participants calculated their Found and Retrieved Time (FART) Score, or the number of days it took to pass the Lego. The research appears in The Journal of Paediatrics and Child Health.

It turns out that for most of the participants, it took an average of 1.71 days for the Lego heads to travel through the digestive tract. There was also no apparent correlation between the SHAT and FART scores. But there was one concerning result: For one unfortunate subject, the Lego head never reappeared.

“Perhaps one day many years from now, a gastroenterologist performing a colonoscopy will find it staring back at him,” the team writes on their blog.

The upshot of the study is that, at least for adults, the toy object seemed to pass through with no complications. But as they write on their blog, the team cautions that the study was really just a bit of fun before the holidays and that it does not apply to children who swallow bits of toys. The sample size was also small, making the study of questionable value to the adult population as well. (Stepping on a Lego, however, is a different story.)

Still, it’s probably best to avoid swallowing Legos or toys of any sort when possible and to schedule a colonoscopy after age 45, just to make sure everything remains awesome.