Pauline Hanson’s concern about the Australian Tax Office installing squat toilets to cater for its increasingly diverse workforce has prompted debate about the best way to go to the toilet: sitting or squatting.
The flush toilet was first invented in the late 16th century by Sir John Harington. But it was only during the 19th century that seated toilets became available for mass use. Most of the Western world still sits to defaecate, while squatting is favoured in the developing world.
Social psychologist Amy Cuddy has some advice for what do in the bathroom before an interview. (Post continues after video.)
The process of passing bowel motions or defaecation is a lot more complicated than you might imagine. First, the rectum contracts as it fills up with stools. This causes the smooth muscle of the anal canal to relax.
The puborectalis muscle, which loops around the rectum like a sling, normally pulls the rectum forward to create a tight angle (known as the anorectal angle). During defaecation, the puborectalis muscle will relax and the anorectal angle will widen.
Squatting widens the anorectal angle even more to allow a clearer and straighter passage for stools to pass through the anal canal.
Experiments have been carried out on the differences between squatting and sitting. Israeli researcher Dov Sikirov studied 28 healthy volunteers who were asked to record how long their bowel motions took and how difficult their efforts were.
The volunteers sat on toilets of different heights (42cm and 32cm high) and also squatted over a plastic container. They recorded data for six consecutive bowel motions in each posture.
Check out bridal fashion made with toilet paper. (Post continues after gallery.)
A Japanese study looked at six volunteers who had their rectums filled with contrast solution and were asked to release the fluid from a sitting and squatting position. They were filmed with live radiography from behind a screen.
The researchers found the anorectal angle had greater widening in the squatting position. Participants also had less abdominal straining while squatting.
People who strain excessively are more prone to developing tears of the anal lining, known as a fissure. One study in Pakistan looked at participants who had chronic anal fissures with symptoms such as painful defecation, passage of blood from the rectum and difficulty sitting.