Science Explains Why Shopping Triggers The Urge To Poop

Have you ever been out shopping when nature suddenly calls? Don't worry, you're not alone. In fact, the need to use the bathroom can hit unexpectedly easily during this particular activity. 

Shopping is a surprisingly robust area of scientific research. We've already told you what science has to say about why people don't return their shopping carts, and covered the psychology of Black Friday, now let's delve into the fascinating subject of needing to poop while shopping — a truly pressing issue, even though its root causes aren't always easy to pin down. As gastroenterology expert Dr. Joseph "The Stomach Doc" Salhab told Today, the sudden need to defecate while in a retail store can be activated in several different ways, which are all connected to your mind. For instance, the body might associate the smells of certain stores with a green-light signal for an urgent bowel movement.

Both stress and relaxation can trigger the need to poop, so if you find shopping uncomfortable, you might experience anxiety poops. On the other hand, gastroenterologist Dr. Kyle Staller of Harvard Medical School and Massachusetts General Hospital points out that people who find certain retail spaces relaxing may just as easily find themselves needing to go. "There could also be psychological conditioning at play if someone associates these spaces with relaxation or comfort," Dr. Staller told Today.

The need to poop while shopping is something people have known about for decades. In 1985, this experience received a name when the Japanese magazine Hon no Zasshi published a letter from one Mariko Aoki, who detailed a personal account of needing to poop while shopping in a bookstore. The response was overwhelming enough that the magazine soon devoted a 14-page article to the subject, which became known as the Mariko Aoki phenomenon. 

The phenomenon has birthed multiple hypotheses. Some brush off the aforementioned relaxation and stress response explanations as confirmation bias – people looking for explanations for their personal ideas of a phenomenon that may not even exist. Others speculate that the brain associating books and sitting on the toilet might explain the Mariko Aoki phenomenon, or that the comparative lack of facilities in a retail store might stress-trigger a bowel movement.

Still, the fact remains that the gastrointestinal system and the brain are very closely connected, which means that the truth about gut feelings is much more complicated than you might think. As Dr. Staller points out, this connection may be in play when a person needs to poop while shopping. "While your colon (the storage space for stool) is always moving to some extent, it really only becomes active at certain times," he told Today. "The trigger for these contractions comes from neurologic signals, either in the brain or from the stomach."