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.”
OWING 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.
106
Why an entire book about rectal alimentation? Because, said Bliss, it is “more interesting than any romance.”
107
The priestly handbook