Gulp: Adventures on the Alimentary Canal

“Right, Alan?”


Kligerman stirred his chili. “I don’t know, Len. I don’t know what the ultimate fate of a suppressed fart is.”

RECTAL TUBES AND breath hydrogen bags have their drawbacks, but either is an improvement on the original methodology. One of the earliest flatus studies on record was carried out by the Parisian physician Fran?ois Magendie. In 1816, Magendie published a paper entitled “Note on the Intestinal Gas of a Healthy Man.” The title is misleading, for although the man in question suffered no illness, he was dead and missing his head. “In Paris,” Magendie wrote in Annales de Chimie et de Physique, “the condemned ordinarily, one hour or two before their execution, have a light meal.” With red wine. So French! “Digestion is thus fully active at the moment of their death.” From 1814 to 1815, the city fathers of Paris, seeming also to have lost their heads, agreed to release the bodies of four guillotined men to Magendie’s lab for a study on the chemical makeup of flatus. One to four hours after the blade had dropped, Magendie extracted gas from four points along the digestive tract and measured what he could.

One of the prisoners Magendie “opened” had consumed lentils as part of his last meal. I would have expected this man to have had the highest hydrogen level—legumes, as we just learned, being the largest supplier of unabsorbed carbohydrates to hungry colon bacteria. Oddly, the highest hydrogen level came out of the prisoner who had eaten “pain de prison et du fromage de Gruyère.” Gruyère cheese and “prison bread.” Were Paris jailers serving some sort of early French precursor to Nutraloaf? Probably not. For many people, unabsorbed carbohydrates from wheat are a sizable contributor to gas. And if you’re going to be dead in two hours, there’s no reason not to fill up on bread.

What amazed me about Magendie, aside from his zest for gore, was this: using instruments available in 1814, he was able to detect hydrogen sulfide, a gas that typically makes up one-ten-thousandth of the gas produced in the human colon. It’s possible the instrument Magendie used was, in fact, his nose. The human olfactory system detects the rotten-egg smell of hydrogen sulfide at the practically nonexistent rate of .02 parts per million. Though present in no more than trace amounts, hydrogen sulfide is, in the words of Michael Levitt, “the most important determinant of flatus odor.” He would know.



* * *



* AkPharma has since sold the Beano brand to pharma giant GlaxoSmithKline. As part of a marketing campaign, GSK’s website included an online University of Gas. Hoping to matriculate—or at least buy a sweatshirt—I clicked on the video. The stately campus building in the background was instantly familiar to me as Baker Library at Dartmouth College, where my parents once worked. Given what I know of the Dartmouth frat scene, it was kind of apt, but I ratted GSK out anyway. The president’s office did not seem to share my outrage (“At this time, I don’t have a comment from President Kim about the Beano University of Gas”), but a cease-and-desist letter eventually went out, and the image was removed.

* But one example of the sly marketing genius of AkPharma. Beano was also the sponsor of a team of hot air balloonists in a prominent race.

* ?ti teG

? I brought Levitt a scrap of notebook paper covered with hash marks, the score card of an anonymous family member who kept track for two days, totaling thirty-five and thirty-nine. “Yeah,” Levitt said, “every time I give a talk someone comes up and tells me twenty-two is way too low.”






14

Smelling a Rat

DOES NOXIOUS FLATUS DO MORE THAN CLEAR A ROOM?



MICHAEL LEVITT DID not set out to make his mark on the world by parsing the secrets of noxious flatus. His fellowship advisor had the idea. The gas chromatograph had just come into use as a laboratory tool, and no one had yet had the ingenuity—or nerve—to apply the technology to human emissions. “He called me into his office,” Levitt recalls. “He said, ‘I think you ought to study gas.’ I said, ‘Why’s that?’ He said, ‘Because you’re pretty much of an incompetent, and this way if you discover anything, at least it’ll be new, and you’ll be able to publish something.’”

Levitt published thirty-four papers on flatus. He identified the three sulfur gases responsible for flatus odor. He showed that it is mainly trapped methane gas, not dietary fiber or fat, that makes the floater float. Most memorably, to this mind anyway, he invented the flatus-trapping Mylar “pantaloon.”

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