As Schweitzer had suggested, his experience was not uncommon for the era. In 1902, Samuel Hutton, a University of Manchester–trained physician, began treating patients at a Moravian mission in the town of Nain, on the northern coast of Labrador, or about as far from the jungles of West Africa as can be imagined, in both climate and the nature of the indigenous population. As Hutton told it, his Eskimo patients fell into two categories: There were those who lived isolated from European settlements and ate a traditional Eskimo diet. “The Eskimo is a meat eater,” he wrote, “the vegetable part of his diet is a meager one.” Then there were those Eskimos living in Nain or near other European settlers who had taken to consuming a “settler’s dietary,” consisting primarily of “tea, bread, ship’s biscuits, molasses, and salt fish or pork.” Among the former, European diseases were uncommon or remarkably rare. “The most striking is cancer,” noted Hutton on the basis of his eleven years in Labrador. “I have not seen or heard of a case of malignant growth in an Eskimo.” He also observed no asthma and, like Schweitzer, no appendicitis, with the sole exception of a young Eskimo who had been “living on a ‘settler’ dietary.” Hutton observed that the Eskimos who had adopted the settlers’ diet tended to suffer more from scurvy, were “less robust,” and endured “fatigue less easily, and their children are puny and feeble.”

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 mellitus, 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.