At last (hic) the answer to a nagging (hic) question

Researcher has theory on why we hiccup

A Queen’s University researcher has come up with an answer to the age-old question: Why do we hiccup?

In a paper published Tuesday in the journal Bio essays, Dr. Daniel Howes hypothesizes that hiccupping is a way of removing swallowed air from the stomach, much like burping. The reflex has given humans and other mammals an evolutionary advantage because it allows suckling infants to consume a greater volume of milk.

Howes, a physician at Kingston General Hospital and associate professor of emergency medicine at Queen’s, has been pondering the question since his undergrad days, when a professor happened to mention that hiccups remain an unexplained phenomenon.

Over the years, Howes came up with the idea that hiccupping was similar to burping, but was still stymied about the purpose of the reflex. The answered dawned on him a couple of years ago, in the wee hours of the morning when he was bottle-feeding his baby daughter.

“I was burping her and after she burped, I could feed her some more. For whatever reason, that’s when it came to me,” he said.

His hypothesis also explains why hiccupping is more common in infants than adults.

Most reflexes can be explained. For instance, sneezing clears irritants from our noses and coughing expels materials from our airways. But hiccupping has always remained an enigma.

There have been many theories over the years, including one suggestion that the involuntary spasm of the diaphragm is a throwback to a time when our ancestors had gills to help them breathe. There have been arguments that hiccups are a form of epilepsy or that they are meant to clear food trapped in the esophagus.

It has also been opined that they are related to fetal development and intended, for example, to strengthen muscles used for respiration or for clearing meconium, the first feces a newborn produces.

While there is no proof that Howes’ hypothesis is the right one, he hopes it will stimulate more thought about the ubiquitous unexplained reflex.