These facts of Europe’s food history lead me to offer the following speculation. Several centuries before the advent of modern medicine, Europeans, like modern Nauruans, may have undergone an epidemic of diabetes that resulted from the new reliability of adequate food supplies, and that eliminated most diabetes-prone bearers of the thrifty genotype, leaving Europe with its low prevalence of diabetes today. Those gene-bearers may have been undergoing elimination in Europe for centuries, as a result of many infants of diabetic mothers dying at birth, diabetic adults dying younger than other adults, and children and grandchildren of those diabetic adults dying of neglect or reduced material support. However, there would have been big differences between that postulated cryptic earlier European epidemic and the well-documented modern epidemics among Nauruans and so many other peoples today. In the modern epidemics, abundant and continually reliable food arrived suddenly—within a decade for Nauruans, and within just a month for Yemenite Jews. The results were sharply peaked surges in diabetes’s prevalence to 20%–50% that have been occurring right under the eyes of modern diabetologists. Those increases will probably wane quickly (as already observed among Nauruans), as individuals with a thrifty genotype become eliminated by natural selection within a mere generation or two. In contrast, Europe’s food abundance increased gradually over the course of several centuries. The result would have been an imperceptibly slow rise in diabetes prevalence in Europe, between the 1400s and the 1700s, long before there were any diabetologists to take note. In effect, Pimas, Nauruans, Wanigelas, educated urban Indians, and citizens of wealthy oil-producing Arab nations are telescoping into a single generation the lifestyle changes and consequent rise and fall of diabetes that unfolded over the course of many centuries in Europe.
A possible victim of this cryptic epidemic of diabetes that I postulate in Europe was the composer Johann Sebastian Bach (born in 1685, died in 1750). While Bach’s medical history is too poorly documented to permit certainty as to the cause of his death, the corpulence of his face and hands in the sole authenticated portrait of him (Plate 28), the accounts of deteriorating vision in his later years, and the obvious deterioration of his handwriting possibly secondary to his failing vision and/or nerve damage are consistent with a diagnosis of diabetes. The disease certainly occurred in Germany during Bach’s lifetime, being known there as honigsüsse Harnruhr (“honey-sweet urine disease”).
The future of non-communicable diseases
In this chapter I’ve discussed just two among the many currently exploding non-communicable diseases (NCDs) linked to the Western lifestyle: hypertension and its consequences, and Type-2 diabetes. Other major NCDs that I haven’t had space to discuss, but that S. Boyd Eaton, Melvin Konner, and Marjorie Shostak do discuss, include coronary artery disease and other heart diseases, arteriosclerosis, peripheral vascular diseases, many kidney diseases, gout, and many cancers including lung, stomach, breast, and prostate cancer. Within the Western lifestyle I’ve discussed only some risk factors—especially salt, sugar, high calorie intake, obesity, and sedentariness. Other important risk factors that I have mentioned only briefly include smoking, high alcohol consumption, cholesterol, triglycerides, saturated fats, and trans fats.
We’ve seen that NCDs are overwhelmingly the leading causes of death in Westernized societies, to which most readers of this book belong. Nor is it the case that you’ll have a wonderful carefree healthy life until you suddenly drop dead of an NCD at age 78 to 81 (the average lifespan in long-lived Western societies): NCDs are also major causes of declining health and decreased quality of life for years or decades before they eventually kill you. But the same NCDs are virtually non-existent in traditional societies. What clearer proof could there be that we have much to learn, of life-and-death value, from traditional societies? However, what they have to teach us is not a simple matter of just “live traditionally.” There are many aspects of traditional life that we emphatically don’t want to emulate, such as cycles of violence, frequent risk of starvation, and short lifespans resulting from infectious diseases. We need to figure out which specific components of traditional lifestyles are the ones protecting those living them against NCDs. Some of those desirable components are already obvious (e.g., exercise repeatedly, reduce your sugar intake), while others are not obvious and are still being debated (e.g., optimal levels of dietary fat).
The current epidemic of NCDs will get much worse before it gets better. Sadly, it has already reached its peak in Pimas and Nauruans. Of special concern now are populous countries with rapidly rising standards of living. The epidemic may be closest to reaching its peak in wealthy Arab oil countries, further short of its peak in North Africa, and under way but still due to become much worse in China and India. Other populous countries in which the epidemic is well launched include Bangladesh, Brazil, Egypt, Indonesia, Iran, Mexico, Pakistan, the Philippines, Russia, South Africa, and Turkey. Countries with lower populations in which the epidemic is also under way include all countries of Latin America and Southeast Asia. It is just beginning among the not-quite 1 billion people of sub-Saharan Africa. When one contemplates those prospects, it’s easy to become depressed.
But we’re not inevitably the losers in our struggles with NCDs. We ourselves are the only ones who created our new lifestyles, so it’s completely in our power to change them. Some help will come from molecular biological research, aimed at linking particular risks to particular genes, and hence at identifying for each of us the particular dangers to which our particular genes predispose us. However, society as a whole doesn’t have to wait for such research, or for a magic pill, or for the invention of low-calorie potato chips. It’s already clear which changes will minimize many (though not all) risks for most of us. Those changes include: not smoking; exercising regularly; limiting our intake of total calories, alcohol, salt and salty foods, sugar and sugared soft drinks, saturated and trans fats, processed foods, butter, cream, and red meat; and increasing our intake of fiber, fruits and vegetables, calcium, and complex carbohydrates. Another simple change is to eat more slowly. Paradoxically, the faster you wolf down your food, the more you end up eating and hence gaining weight, because eating rapidly doesn’t allow enough time for release of hormones that inhibit appetite. Italians are slim not only because of their diet composition but also because they linger talking over their meals. All of those changes could spare billions of people around the world the fates that have already befallen the Pimas and the Nauruans.
This advice is so banally familiar that it’s embarrassing to repeat it. But it’s worth repeating the truth: we already know enough to warrant our being hopeful, not depressed. Repetition merely re-emphasizes that hypertension, the sweet death of diabetes, and other leading 20th-century killers kill us only with our own permission.