IS THE DIGESTIVE TRACT A TWO‑WAY STREET?

A S FAR BACK as ancient Egypt and as recently as 1926, patients unable to keep their food down would be given their food up. The “nutrient enema” was a last resort for people who, the thinking went, would otherwise starve. As unlikely as it may sound, the practice was broadly accepted in the medical community, so much so that ready‑made preparations were available for purchase. You would see them advertised in the pages of journals, complete with the occasional customer testimonial (as from the satisfied 1859 patient for whom rectal coffee[104]and cream “relieved the sense of ‘famishing thirst’ better than any other injection”).

President James Garfield was the poster boy of rectal feeding. In 1881, Garflield’s liver was pierced by an assassin’s bullet and shortly thereafter inoculated with a dose of bacteria from the unwashed fingers and instruments of Dr. D.[105]W. Bliss. From August 14 to the time of Garfield’s death on September 19, the dwindling, retching head of state, on Bliss’s orders, was fed nothing but nutrient enemas prepared in the dispensary of the United States surgeon general.

Here is the recipe for Assistant U.S. Surgeon General C. H. Crane’s Rectal Beef Extract: “Infuse a third of a pound of fresh beef, finely minced, in 14 ounces of cold soft water, to which a few drops of muriatic acid and a little salt… have been added. After digesting for an hour to an hour and a quarter, strain it through a sieve.” The yolk of an egg was then added, along with 2 drams of Beef Peptonoids and 5 drams of whiskey.

The nice thing about cooking for someone who can’t taste the food is that the same dish can be served over and over without complaint. Or without the usual complaint. A downside to eating rectally is that body heat quickly leads to rot and reek. President Garfield and his nurses endured five days of sulfurous flatus so “annoying and offensive” that egg yolks were stricken from the recipe. Beef blood was likewise to be avoided; one physician lamented that the odor produced by decomposing blood was “so offensive as to pervade the whole house.” Bouillon, another common rectal menu item, also created optimal conditions for bacteria. (Before agar was widely used for laboratory cultures, a medium of choice was beef broth.) The enema‑fed rectum was a highly efficient incubator, an in‑house petri dish.

What’s worse, proceeding too quickly could trigger the more traditional goal of the enema. (I suppose it wasn’t that far removed from feeding a baby. Though where do you hang the bib?) “I need hardly say,” wrote a learned contributor to the British Medical Journal in 1882, “that the rectum should be empty when a nutrient injection is to be given.” A before‑dinner enema of the cleansing variety was recommended.

As a way around the problem, food could be mixed with wax and starch to form a suppository. An additional advantage of this, wrote Bliss in Feeding per Rectum ,[106]was that patients could manage their own feeding and need not be confined to the hospital. “The convenience of this method is very great,” he enthused. It was the Clif Bar of rectal alimentation. Bliss followed with a caveat: “In some cases, owing to irritability of the rectum, the whole suppository has been returned.” In the history of medicine, has a gentler euphemism ever been coined for the act of excretion? Excuse me, here you go, I’m returning this?

Eventually Heschl and Dawson and the others came along, hosing their cadavers and publishing their papers. The ileocecal valve experiments made it clear: the small bowel–the homeland of nutrient absorption–was, under normal, nonhydraulic circumstances, unreachable via reverse passage. This is why the meat preparations tended to include some minced pancreas. The hope was that the pancreatic enzymes would break down proteins into something more readily absorbed by the colon and rectum.

Did rectal feeding provide nourishment or just hydration? What–and how much–was being absorbed? A round of experiments got under way, and it soon became clear that the colon and rectum were incapable of absorbing large molecules: fats, albumins, proteins, all of it was returned a few days later. Salt and glucose, some short‑chain fatty acids, a few vitamins and minerals, these things were retained to a certain extent. And little else. Ninety percent of nutrient absorption takes place in the small intestine. Rectal meals could postpone death, but it was an exaggeration to say they sustain life.

Interestingly, the Vatican proposed a similar experiment in the 1600s. The Church sought an answer to the nagging question “Does rectal consumption of beef broth break one’s Lenten fast?” This was a subject of some controversy within the Church. Pharmacists of the day were turning a brisk business administering bouillon enemas to nuns and other pious, peckish Catholics who found that this helped them make it to lunch. The Vatican rules on fasting define food as “something digestible, received from outside into the mouth and passed by swallowing into the stomach.” By this definition, an enema does not technically break one’s fast.[107]Enema madness in the convents was forcing the Vatican to reconsider. An experiment was proposed whereby volunteers would be fed strictly by rectum. If they survived, the enema would have to be considered food and therefore banned. If they didn’t, the definition would remain as is, and some vigorous penance would be in order. In the end, nobody volunteered and the nuns continued, wrote Italian medical historian A. Rabino, to “welcome the clysters in their cells with tranquil conscience.”

O WING TO THE limited talents of the colon as an organ of absorption, perfectly good nutrients are daily discarded. The small intestine has time to absorb only so much before passing the goods along to the colon. Bacteria in the colon break down what they can, creating vitamins and other nutrients in the process, but because the colon isn’t as well set up to absorb the locally produced bounty, some of it is excreted.

This topic came up during a conversation with pet‑food scientist Pat Moeller, of AFB International (and chapter 2). Moeller had offered an explanation for the disconcerting canine habit of autocoprophagia. “If you think about it”–and, improbably, we were–“a dog that eats its stool, in some cases, may be getting missing nutrients” by running a meal through the small intestine twice.

In some neighborhoods of the animal kingdom, your own is a regular second course. For rodents and rabbits, in whom vitamins B and K are produced exclusively in the colon (by bacteria that live there), the self‑manufactured pellet is a large, soft daily vitamin. Which brings us to Richard Henry Barnes and a little‑known chapter of nutrition history.

Richard Henry Barnes was the dean of the Graduate School of Nutrition at Cornell University from 1956 to 1973, the president of the American Institute of Nutrition, and the first academic to formally address the consumption of shit. I found a photograph of Barnes taken around the time his “Nutritional Implications of Coprophagia” ran in Nutrition Reviews . His blond hair had receded from his temples and was combed flat against his skull. His glasses were the two‑toned horn rims popular in the late 1950s. Ed Harris could play the part. Barnes did not appear to be in any part an iconoclast. “One of the qualities I respected most in Dick,” a colleague reminisced in a Barnes obituary, “was his complete open‑mindedness and objectivity in dealing with… socially and politically sensitive questions.”

Barnes’s original interest in rodent autocoprophagia grew out of efforts to prevent it. Like other nutritionists of his day, Barnes was frustrated to find his carefully controlled diet studies repeatedly undone by his subjects’ menu substitutions. Experimenters before him had tried building cages with wire‑mesh flooring that allowed fecal pellets to drop through. This proved to be of limited use because, quoting Barnes, “feces are consumed as they extrude from the anus.” Rats on mesh floors still managed to consume anywhere from 50 to 65 percent of their “total output.”

Presently Barnes became more interested in the inputting of output than in the elements of nutrition he’d originally set out to study. “The contributions of coprophagy in rats as a means of making available the nutrients that are synthesized in the lower intestine has remained one of the major nutritional mysteries of our time,” he wrote in a 1957 paper funded by, holy shit, the National Science Foundation (NSF).

Barnes began by documenting the precise extent to which egesta made up his rats’ daily fare. This he did by fashioning “feces collection cups” from the necks of small plastic bottles and fitting them over the rat’s tail and rear end. And here we get a glimpse of the industriousness and creativity of Richard Henry Barnes. Part of that NSF grant went to cover the cost of a band saw, Forstner drill bit, wood chisel, Scotch tape, metal bands, rubber tubing, and three different sizes of plastic bottles from the Wheaton Plastics Company. Daily collections were emptied from the cup and served to the animal in its feed jar, which I like to picture with a silver warming cover, lifted with a flourish by Barnes himself. The rats, Barnes found, ate 45 to 100 percent of what they’d excreted each day. If you prevent a rat from doing this, Barnes further noted, it will quickly become deficient in vitamins B5, B7, B12, and K, thiamine, riboflavin, and certain essential fatty acids.

Four years later, B. K. Armstrong and A. Softly, scientists with the Department of Biochemistry and the Animal House at Royal Perth Hospital, showed that preventing rats from eating their first round of excreta severely stunted their growth. Over the course of a forty‑day experiment, young rats thusly stymied gained just 20 percent of their starting body weight, while an unhindered control group gained 75 percent. (Both groups ate all their other food as well.) Armstrong and Softly developed their own unique method of restraint, eschewing the Barnes technique. “To eliminate the necessity for continual emptying and replacement of fecal cups, we have used a jacket to prevent the rat from reaching its anus.”

“Used a jacket” is a humble understatement. A pattern (included in the journal paper) was drawn up and soft purse leather purchased. “A V‑shaped tail cleft was trimmed to clear the penis or vagina. The laces were adjusted to give a firm, but not tight fit, and the string was tied at the tail in a knotted bow. Final adjustments were made with fine scissors.” It all sounds very Stuart Little until you turn the page and come upon plate 1: “Rats wearing jackets to prevent coprophagy.” The leather is black, and the jacket, actually a vest, is laced along the animal’s midline like a corset. An attached black leather collar completes the look. Suddenly “restraint” took on a whole new flavor, and you began to wonder what went on after hours at the Animal House.

Barnes likened autocoprophagia to rumination: another strategy to get the most out of one’s meal. Cows will rechew and reswallow the same mouthful forty to sixty times, greatly increasing the surface area that rumen bacteria have to work with and extracting maximum nutritive value. In fact, one of the alternate terms for autocoprophagia is “pseudo‑rumination.” No doubt the word was coined by a rabbit fancier. Rabbits are diehard autocoprophagics, and their owners seem a little uncomfortable with it. In rabbit circles, the first round’s larger, softer fecal pellets[108]have a special, non‑fecal‑sounding name: cecotropes. “Cecotrophy, not Coprophagy,” tuts a heading in one journal paper.

“It seems likely that most nonruminant species have a voracious appetite for feces,” Barnes bravely continued. “This practice is so normal to their nutritional behavior that the… large intestine should rightfully be considered as functionally positioned ahead of the absorptive region of the intestinal tract.” In other words, a second visit to the small intestine is the true end point for absorption.

I will buy that autocoprophagia is, as Barnes put it, “a normal practice for… rats, mice, rabbits, guinea pigs, dogs, swine, poultry, and undoubtedly many others.” But Richard: “Most nonruminant species”?

Let’s check in first with our closest cousins. I e‑mailed Jill Pruetz, the Iowa State University primatologist whose work with chimpanzees in the Fongoli River region of Senegal I profiled for a magazine in 2007. By coincidence, Pruetz and her colleague Paco Bertolani had just submitted a paper on the topic. “I don’t like to think of the Fongoli chimps as shit‑eaters,” she wrote back, “but what are you going to do?” For one thing, you call it “seed reingestion.” Technically speaking, this is accurate. Fongoli chimps don’t, as they say, “consume the dung matrix.” They “excrete a faecal bolus into one hand and then extract the seeds from it with the other hand or with the lips.” You may be pleased to note that when they are done they “clean their lips by rubbing them on the bark of trees.”

Pruetz’s team observed seed reingestion only during the span of weeks when baobab and Fabaceae seeds are too hard to chew. During this time, it takes a second run through the digestive tract to dissolve the hulls and release the proteins and fats in the kernel. Women in the Tanzanian Hadza tribe use a similar technique, harvesting softened baobab seeds from baboon dung, washing and drying them, and pounding them into a kind of flour.

Before you get all high and mighty on the chimps and the Hadza, you should know that the most expensive coffee beans in the world–at upwards of two hundred dollars a pound–are those that have passed through the digestive tract of the civet, a catlike animal native to Indonesia. The animal’s digestive enzymes are said to alter the taste of the beans in a pleasing manner. The trade is lucrative enough to have spawned a market for counterfeit civet dung, crafted from ordinary undigested coffee beans, a dung matrix of similar consistency, and glue.

Though seed reingestion is most prevalent on the savannah, where food is scarcer, it also happens in the rain forest. Pruetz’s paper cites the work of a team of researchers who observed coprophagy in wild mountain gorillas. At a loss to explain the behavior, given the relative bounty of the surroundings, the researchers suggested that it might have been done for the same reason people reach for the Cream of Wheat on a midwinter morning. “They proposed,” Pruetz wrote to me in an e‑mail, “that mountain gorillas might like to eat something warm during periods of cold temperatures or heavy rain.”

And now, with all apology, it’s time to move on to Homo sapiens . A 1993 study of “humans behaving in a manner similar to nutrient‑deficient animals” involved three institutionalized patients, Bart, Adam and Cora, all with profound developmental disabilities. Charles Bugle and H. B. Rubin successfully broke the trio’s autocoprophagia habits by feeding them a nutritional supplement drink called Vivonex. The authors speculated that this population “often has multiple handicaps and something may be missing that makes it more difficult to digest or metabolize all the nutrients in the diet they are served.” Whether or not this is true, a glass of Vivonex is preferable to some of the alternative strategies tried by staff at other institutions. In particular, that of the team who “treated… coprophagia and feces‑smearing by making a shower contingent upon the absence of feces.” You can see where that could go south pretty fast.

T HERE IS ONE class of substances that the rectum, even today, is occasionally called on to absorb. Drugs take effect faster this way than by mouth, partly because they bypass the stomach and liver. Opium, alcohol, tobacco, peyote, fermented agave sap, you name it–it’s been taken rectally. In the case of certain South American hallucinogens, rectal indulgence also allows one to sidestep vomiting that accompanies the oral route. Considerably enlivening the pages of Natural History in March 1977, Peter Furst and Michael Coe described the heretofore unrecognized prominence of the “intoxicating enema” in classic Mayan culture. The discovery came about with the examination of a painted Mayan vase from circa 3 A.D. that had previously been hidden away in a private collection. The decorative embellishments feature a man in an elaborate pointy hat but no pants, crouched like a cat, hind quarters raised, while a kneeling consort holds a tubular object to his anus. Another man squats, administering to himself.

Access to the vase brought a thunderclap of realization. “Previously enigmatic scenes and objects in classic Maya art” suddenly made sense. Furst and Coe give the example of a small clay figurine, found in a tomb, of a squatting man reaching back as though to wipe himself. Experts had been puzzled. Why would family members bury a loved one with the Maya equivalent of Manneken Pis? Now it was clear. The man was on a ritual bender. Images on the vase no doubt also helped crack the enigma of what had appeared to be rustic, hand‑hewn turkey basters–hollow bones with animal or fish bladders attached at one end–turning up at archaeological digs all over South and Central America. “South American Indians,” observe Furst and Coe, “were the first people known to use native rubber‑tree sap for bulbed enema syringes.”

Is it not possible that the images on the vase depict a simple laxative procedure? Furst and Coe address this, insisting that only partakers of the “Old World enema” were concerned with constipation. (Sometimes to excess. The authors note that Louis XIV had more than two thousand clysters during his reign, sometimes “receiving court functionaries and foreign dignitaries during the procedure.” The Louis passion for the syringe can be traced through the lineage as far back as XI, who had enemas administered to his dogs.)

The southern route has advantages as well for administering poisons. Bypassing the taste buds–and the court taster, if such an entity actually existed–allowed murderers to get away with a higher dose. Some historians believe the Roman emperor Claudius was killed in this manner, at the behest of his fourth wife, the fetching and far younger Agrippina. Ostensibly the motive was political. Agrippina was in a rush to install her son from a previous marriage as Rome’s emperor. There was also this, courtesy of Suetonius: “His laughter was unseemly and his anger still more disgusting, for he would foam at the mouth and trickle at the nose; he stammered besides and his head was very shaky.” And this, from the September 5, 1942, issue of the Journal of the American Medical Association : “The emperor Claudius… suffered from flatulence.”[109]

By far the oddest reverse delivery on record is the holy‑water enema. The first reference I came upon, a passing mention in an art journal, suggested that the holy‑water clyster was a routine weapon in the exorcist’s arsenal. This made a certain amount of sense: Why sprinkle the possessed with holy water when you can pump it right up inside them? Seeking to verify the practice, I e‑mailed the public relations office of the United States Conference of Catholic Bishops, the stateside headquarters of the Catholic Church. Naturally this went unheeded. Returning to the art journal, I consulted the article’s references, ordered a copy of the cited paper, and hired a translator, as it had been published in an Italian medical journal.

The holy‑water enema, by this account, was an isolated case, involving Jeanne des Anges, the mother superior of an Ursuline convent in Loudun, France, in the early 1600s. Des Anges claimed that the parish priest, a raffish, high‑ranking charmer named Urbain Grandier, was appearing to her in her dreams, caressing her and attempting to seduce her. He seemed to be having some measure of success, as the contemplative quiet of the convent was being shattered by the mother superior’s nightly shrieks of sexual frenzy. An exorcism was promptly ordered.

Why would one administer the blessed liquid rectally instead of simply having the possessed drink a glass of it? One explanation is that the original Roman Catholic rite for the Blessing of the Holy Water included adding salt to the water. Regardless of the origins of the practice, this had the effect of rendering it undrinkable.[110]

Here’s the other reason: “After many days in which the priest tried to dispel the devil, he learned from the possessed mother superior that the devil had barricaded himself inside…” Here my translator stopped. She leaned closer to the photocopied pages and traced the words with her finger. “…il posteriore della superiora . Inside her butt!”

Sensing that the situation had progressed beyond his expertise or comfort level, the exorcist called for outside help in the form of a pharmacist, “Signor Adam,” and his traveling syringe. (Enemas in those days were the purview of pharmacists and comprised a sizable percentage of their income.) Mr. Adam “filled up the syringe with holy water and gave the miracle clyster to the mother superior, with his usual skill.” Two minutes later the devil had vamoosed.

Books about the Loudun fracas, including a 1634 translation of an account by “an eyewitness,” include no mention of Mr. Adam or rectal exorcism, but they do serve to flesh out the story. Grandier was convicted of sorcery and burned at the stake, and most sources agree he’d been framed by des Anges, acting in cahoots with a rival priest. The “possessions” continued for several years after the execution, spreading to sixteen other nuns and turning the convent into a local tourist attraction, and understandably so: “They… made use of expressions so indecent as to shame the most debauched of men, while their acts, both in exposing themselves and inviting lewd behavior… would have astonished the inmates of the lowest brothels in the country.”

In the words of my translator Rafaella, responding to the material I had engaged her to read, “I am sorry, but nuns should be allowed to have sex.” Or at least an occasional holy‑water enema.

• • •

A ROUND THE TIME doctors took to serving dinner through “the other mouth”–as Mütter Museum curator Anna Dhody has called the anus–a phenomenon called antiperistalsis began cropping up in medical journals. This was distinct from the fleeting reverse‑peristaltic lurch of vomiting, wherein the small intestine squeezes its contents backward into the stomach, whose sphincters have opened to grant through‑passage. That is normal.

This is not. “For eight days this person, at least once and sometimes twice in twenty‑four hours, vomited veritable feces, solid, cylindrical, of a brown color and with the normal faecal odor, coming evidently from the large intestine.” The patient was a young woman, admitted to a hospital in Lariboisière in 1867, under the care of a Dr. Jaccoud, for a bout of hysterical convulsions. This was not the first alleged case of “defecation by the mouth.” Writing in 1900, Gustav Langmann summarized eighteen case reports of widely varying plausibility.

Jaccoud assumed his patient had an intestinal obstruction. When digesta backs up to the point that it threatens to burst the pipes, an emergency measure called “faeculent vomiting” kicks in. But the material in that case is highly liquid, coming, as it does, from the small intestine. A well‑formed stool does not exit the upper end of the colon.

Besides, the woman showed no symptoms of a life‑threatening obstruction. “Apart from the passing disgust which followed the act,” Jaccoud noted, “the patient ate as usual and continued in her ordinary health.” Things simply appeared to be running in reverse. Jaccoud’s colleagues suspected he’d been had. Defecation by mouth was a showstopper in the tradition of stomach snakes or the birthing of live rabbits (which turned out to have been sequestered in the woman’s skirts). Experts would travel great distances to observe a spectacle of this caliber. For the lonely or neglected patient who craves attention, it was just what the doctor ordered.

In 1889, Gustav Langmann put an alleged reverse‑defecator to the test. A twenty‑one‑year‑old schoolteacher, identified as N.G., had been admitted to the German Hospital of New York on and off for over a year, with the complaint of repeated spells of vomiting. On May 18 of that year, witnesses reported she threw up “hard scybala” the size of malted‑milk balls. “It seemed,” wrote Langmann in his paper, “to be a favorable time to experiment in regard to the carriage of substances from the rectum to the mouth.”

At 11:01 A.M., Dr. Langmann injected just under a cup of water tinged with indigo dye into the woman’s rectum. “Blue feces took its natural course,” which is to say it emerged from the customary direction. A few days later, a nurse reported having discovered “some hard feces, wrapped in paper,” under the woman’s pillow. Langmann reports that she later tried her “tricks” at two other medical facilities.

Human beings do not defecate through the same orifice they eat with. That is a feat reserved for the cnidarians[111]–sea anemones and jellyfish being the best‑known examples.

Contributing to the confusion about “antiperistalsis” was the fact that the normal waves of intestinal peristalsis run in both directions. It’s a mixing function. The better the digesta circulate, the more nutrients come in contact with the villi. Though the net movement is forward, it is, as Mike Jones put it, a “two‑steps‑forward‑one‑step‑back phenomenon.”

Look up antiperistalsis in the medical literature, and you will come across a brief, curious phase in the history of surgery. In 1964, a team of northern California surgeons took an ambitious and iconoclastic approach to curing chronic diarrhea and improving absorption. To slow forward transit through the small intestine, they removed a six‑inch segment of it, turned it around, and stitched it back in place.

Jones points out that the body has a tendency to rewire itself as it sees fit. A 1984 study followed four patients who’d had the operation. Within two years, the diarrhea had returned.

For milder cases, a shift of perspective may be helpful. “When I see a patient with a little bit of diarrhea,” Michael Levitt told me, “I say, ‘Just be happy you’re not constipated.’”

16. I’m All Stopped Up