Herbivore vs. carnivore

Vegetarianism has long been associated with a host of heterodox preoccupations, including nudism, teetotaling, communitarianism and other utopian schemes, free love, idiosyncratic religions, bizarre health regimens and the violent overthrow of the state. The first eminent vegetarian Stuart dusts off is an acolyte of the great 17th-century scholar Sir Francis Bacon, Thomas Bushell, who in his youth was unfortunate enough to become tarnished in a smear campaign by Bacon's political enemies; they accused Bacon of paying Bushell for sex. After Bacon's death, the distraught Bushell plunged into dissipation before throwing it all over for the austere lifestyle his mentor had advocated, subsisting on bread and water and retiring to his estate in Oxfordshire. In his old age, he entertained visitors on the grounds; "There," one reported, "he had two mummies; [and] a grott[o] where he lay in a hammock like an Indian." (One of the mummies, a rare Egyptian specimen, was a gift from Queen Henrietta and soon rotted away in the moist grotto.)

Bacon had also concocted a plan to start an "ideal colony" in 3-mile-deep caves, where the inhabitants would be fed only on "a fermented meat drink." Bushell adapted this scheme for a silver mine that he owned in Wales, providing a dining hall that served the miners only bread and water, which must have seemed painfully meager to men who didn't spend their days lying in a hammock. As it is, it's hard to believe Bushell could have survived on such a regimen. The question of what exactly historical vegetarians ate is one that never gets sufficiently addressed in "The Bloodless Revolution." Another 17th-century vegetarian reported feasting on "broth thickned with bran, and pudding made with bran, & Turnep leaves chop't together, and grass." Very rarely, Stuart clarifies such statements by explaining, for example, that the term "herbs" sometimes included cabbage, but no further insight is offered into this particular gentleman's startling claim to have eaten grass.

Conventional wisdom held that meat was essential to proper nutrition, but all early vegetarians insisted on the superior health-giving properties of their diets. To evaluate this controversy, it would be invaluable to know what exactly the average middle-class European ate every day and what specifically the vegetarians recommended instead. What sorts of fresh vegetables were available? How common were dishes of grains, beans, nuts and legumes? Anyone who has read the intimate letters of 18th- and 19th-century men and women will recall how often they complain of constipation (the James brothers, Henry and William, being prime examples), so it's possible that high-fiber vegetarian diets prescribed by evangelical doctors like the celebrated George Cheyne really did work wonders. (Although the widespread medicinal use of opium might have also been to blame for the problem.) I once heard the novelist Neal Stephenson observe that bladder stones, a common and life-threatening 17th-century ailment that's extremely rare today, might have resulted from the dehydration of city dwellers who dared not trust the local water supply. More vegetables might have helped with that, too.

No one seems to know why bladder stones have vanished as a health problem in developed countries, though, and it's quite possible that Stuart simply couldn't find out what constituted the typical nonvegetarian diet of these various historical periods. We may never know what, exactly, the vegetarian quoted above meant by "grass." Still, if Stuart tried and failed to establish any of this, he doesn't mention it. This lack of context makes the book's many, repetitive accounts of the health claims made by different vegetarian champions especially tiresome; it's impossible to consider them against any reliable standards of human nutrition. They are cloud-cuckoo theories voiced in a cloud-cuckoo land of fantastical dimensions, like the attributes of Dungeons and Dragons characters.

Pre-20th-century medicine was so wacky and delusional that it's hard to care much about the debates that raged within it. Doctors blamed disease on factors like the accumulation of vapors in various parts of the body, bad air, thinking too hard and the imbalance of humors, and they prescribed bleeding and the ingestion of toxic substances in addition to weird diets, of which vegetarianism -- often dubbed "the milk diet" -- was only one. When you learn that Cheyne thought epilepsy was caused by "hydraulic blockages in the blood and nerves" and that ingested meat left behind salt crystals whose tiny sharp edges would poke through the walls of blood vessels, it's hard to be impressed by the one time he came close to the contemporary understanding of cholesterol. When he was right about something, it was almost certainly by accident.

And when he was wrong, as Stuart scandalously suggests, it might have been on purpose. One of Cheyne's more celebrated patients was the publisher Samuel Richardson, who would later go on to write "Pamela," the first novel in the English language. Richardson came to Cheyne complaining of a cold, and Cheyne prescribed him a course of pills that contained mercury. This wasn't unusual -- mercury was commonly administered as a medicine at the time -- but it was dangerous. Mercury, as Stuart explains, is "a virulent neurotoxin" and when introduced into the body in sufficient amounts causes "fits of trembling, twitching, temporary and local paralysis, giddiness, nausea, anxiety, depression, hypersensitivity (erethism) and a tendency to withdraw from social contact." Richardson was soon very sick indeed. Cheyne increased the dosage, and when Richardson got even worse, he prescribed his most radical therapy: a completely vegetarian "milk diet" -- and the cessation of all mercury treatments. Richardson quickly improved, and Cheyne's pet diet took the credit.

As appalling as this story is, Stuart has further discovered that Cheyne already knew that mercury was toxic. The physician admitted that the chemical caused "nervous disorders and paralysis" in his books. "It is hard to believe that Cheyne knowingly poisoned people with mercury until they succumbed to his vegetable diet," Stuart writes, but it is also hard to believe otherwise. At worst, Cheyne was irresponsible, or subscribed to a purgative strategy not unlike that of today's "high colonic" enema buffs, believing that his patients' "corrupt bodies" needed to be violently "cleansed" of the garbage they'd ingested before the "purity" of his vegetarian diet could work its magic.

Stuart suspects that most of the people who pushed vegetarianism as a health regimen also wanted mankind to give up meat eating for moral reasons. It was often hard to disentangle the two, since the foremost authority on how human beings ought to live (and therefore eat) was the Bible. Omnivores pointed to God's admonition to Noah that "every moving thing that liveth shall be meat for you," while vegetarians argued that before the Fall, Adam and Eve were instructed to subsist on "every herb bearing seed" and "the fruit of a tree yielding seed" which "to you ... shall be for meat." Whether or not humanity should or could revert to the prelapsarian diet of Eden was a key point of debate. But because ethical vegetarianism was associated with either religious free-thinking or (in England) crypto-Catholicism, many of those who opted to give up meat for moral reasons tended to present their choice as a medical one in public.

Next page: Could vegetarianism have paved the way back to Eden?