Good Calories, Bad Calories (19 page)

What both Schweitzer and Hutton had witnessed during their missionary years was a “nutrition transition,” a term now commonly used to describe a population’s Westernization in diet, lifestyle, and health status. The World Health Organization recently described the current version of the nutrition transition this way:

Changes in the world food economy have contributed to shifting dietary patterns, for example, increased consumption of an energy-dense diet high in fat, particularly saturated fat, and low in carbohydrates. This combines with a decline in energy expenditure that is associated with a sedentary lifestyle…. Because of these changes in dietary and lifestyle patterns, diet-related diseases—including obesity, diabetes mel itus, cardiovascular disease, hypertension and stroke, and various forms of cancer—are increasingly significant causes of disability and premature death in both developing and newly developed countries.

This is little more than an updated version of the changing-American-diet story Ancel Keys and others had invoked to advocate low-fat diets: we eat fewer carbohydrates and ever more fat then we did in some idealized past, and we pay the price in chronic disease. Keys’s reference point was the American diet circa 1909 (as portrayed by USDA estimates), or the Japanese or Mediterranean diets of the 1950s. When it was suggested to Keys that other nutrition transitions, including those witnessed by Schweitzer and Hutton, could be edifying, he argued that not enough was known about the diets or about the health of those isolated populations for us to draw reliable conclusions. He also insisted that in many of these populations—particularly the Inuit

—relatively few individuals were likely to live long enough to develop chronic disease, so little could be learned.

This argument, too, has taken on the aura of undisputed truth. This could be cal ed the “nasty, brutish, and short” caveat, after Thomas Hobbes’s pithy interpretation of the state of primitive lives. But earlier generations of physicians had the advantage of observing conditions of nutrition and health considerably further back on what anthropologists refer to as the curve of modernization. In this sense, their job was easier: noting the absence of a disease in a population, or the appearance of diseases in a previously unaffected population—the transition from healthy populations to sick populations, as Geoffrey Rose would put it—is an observation less confounded with diagnostic and cultural artifacts than are the comparisons of disease rates among populations al of which are afflicted.

Most of these historical observations came from colonial and missionary physicians like Schweitzer and Hutton, administering to populations prior to and coincidental with their first substantial exposure to Western foods. The new diet inevitably included carbohydrate foods that could be transported around the world without spoiling or being devoured by rodents on the way: sugar, molasses, white flour, and white rice. Then diseases of civilization, or Western diseases, would appear: obesity, diabetes mel itus, cardiovascular disease, hypertension and stroke, various forms of cancer, cavities, periodontal disease, appendicitis, peptic ulcers, diverticulitis, gal stones, hemorrhoids, varicose veins, and constipation. When any diseases of civilization appeared, al of them would eventual y appear.

This led investigators to propose that al these diseases had a single common cause—the consumption of easily digestible, refined carbohydrates. The hypothesis was rejected in the early 1970s, when it could not be reconciled with Keys’s hypothesis that fat was the problem, an attendant implication of

which was that carbohydrates were part of the solution. But was this alternative carbohydrate hypothesis rejected because compel ing evidence refuted it, or for reasons considerably less scientific?

The original concept of diseases of civilization dates to the mid-nineteenth century, primarily to Stanislas Tanchou, a French physician who served with Napoleon before entering private practice and studying the statistical distribution of cancer. Tanchou’s analysis of death registries led him to conclude that cancer was more common in cities than in rural areas, and that the incidence of cancer was increasing throughout Europe. “Cancer, like insanity,” he said,

“seems to increase with the progress of civilization.” He supported this hypothesis with communications from physicians working in North Africa, who reported that the disease had once been rare or nonexistent in their regions, but that the number of cancer cases was “increasing from year to year, and that this increase stands in connection with the advance of civilization.”

By the early twentieth century, such reports had become the norm among physicians working throughout Africa. They would typical y report a few cancers in towns where the “natives mingled with Europeans” and had copied their “dietetic and other domestic practices,” but not in those areas where lifestyles and diets remained traditional. These reports, often published in the British Medical Journal, The Lancet, or local journals like the East African Medical Journal, would typical y include the length of service that the author had undergone among the natives, the size of the native population served by the hospital in question, the size of the local European population, and the number of cancers diagnosed in both. F. P. Fouché, for instance, district surgeon of the Orange Free State in South Africa, reported to the BMJ in 1923 that he had spent six years at a hospital that served fourteen thousand natives. “I never saw a single case of gastric or duodenal ulcer, colitis, appendicitis, or cancer in any form in a native, although these diseases were frequently seen among the white or European population.”

In 1908, the Smithsonian Institution’s Bureau of American Ethnology published the first significant report on the health status of Native Americans. The author was the physician-turned-anthropologist Aleš Hrdli ka, who served for three decades as curator of the Division of Physical Anthropology at the National Museum in Washington (now the Smithsonian’s National Museum of Natural History). In a 460-page report entitled Physiological and Medical Observations Among the Indians of Southwestern United States and Northern Mexico, Hrdli ka described his observations from six expeditions he had undertaken. “Malignant diseases,” he said, “if they exist at al —that they do would be difficult to doubt—must be extremely rare.” He had not encountered

“unequivocal signs of a malignant growth on an Indian bone.” Hrdli ka also noted that he saw only three cases of “organic heart trouble” among more than two thousand Native Americans he examined, and “not one pronounced instance of advanced arterial sclerosis.” Varicose veins were rare, and hemorrhoids infrequent. “No case of appendicitis, peritonitis, ulcer of the stomach, or of any grave disease of the liver was observed,” he wrote.

Hrdli ka considered the possibility, which Keys would raise fifty years later, that these Native Americans were unaffected by chronic disease because their life expectancy was relatively short; he rejected it because the evidence suggested that they lived as long as or longer than the local whites.

In 1910, Hrdli ka’s field observations on cancer were confirmed by Isaac Levin, a Columbia University pathologist, who surveyed physicians working for the Indian Affairs Bureau on reservations throughout the Midwestern and Western states. Levin’s report, entitled “Cancer Among the North American Indians and Its Bearing upon the Ethnological Distribution of the Disease,” discussed the observations of 107 physicians who had responded to his survey, with their names, locations, size of practice, duration of practice, and number of cancers diagnosed: Chas. M. Buchannan, for instance, practiced fifteen years among two thousand Indians with an average life expectancy of fifty-five to sixty years and saw only one case of cancer; Henry E. Goodrich, practicing for thirteen years among thirty-five hundred Indians, saw not a single case. Levin’s survey covered over 115,000 Native Americans treated by agency doctors for anywhere from a few months to two decades and produced a total of twenty-nine documented cases of malignant tumors.

The two most comprehensive attempts to deal with the question of cancer in isolated populations were in The Natural History of Cancer, with Special Reference to Its Causation and Prevention, published in 1908 by W. Roger Wil iams, a fel ow of the British Royal Col ege of Surgeons, and The Mortality from Cancer Throughout the World, published in 1915 by the American statistician Fredrick Hoffman. In The Natural History of Cancer, Wil iams marched from continent to continent, region to region. In Fiji, for instance, in 1900, among 120,000 aborigines, Melanesians, Polynesians, and

“Indian coolies,” there were only two recorded deaths from malignant tumors. In Borneo, a Dr. Pagel wrote that he had been in practice for ten years and had never seen a case. Wil iams also documented the rising mortality from cancer that Tanchou had reported in the developed nations. In the United States, the proportional number of cancer deaths rose dramatical y in the latter part of the nineteenth century: in New York, from thirty-two per thousand deaths in 1864 to sixty-seven in 1900; in Philadelphia, from thirty-one in 1861 to seventy in 1904.

Hoffman dedicated the better part of his career to making sense of these observations. He began his cancer studies as chief statistician of the Prudential Insurance Company and continued them as part of an investigation of the Committee on Statistics of the American Society for the Control of Cancer (a predecessor of the American Cancer Society, of which Hoffman was a founder). In The Mortality from Cancer Throughout the World and then again in Cancer and Diet, his 1937, seven-hundred-plus-page update of the evidence, Hoffman concluded that cancer mortality was increasing “at a more or less alarming rate throughout the entire world,” and this could only partial y be explained by new diagnostic practices and the aging of the population.