What is the Nutrition Transition?

Two historic processes of change precede or occur simultaneously with the nutrition transition. One is the demographic transition: the shift from a pattern of high fertility and high mortality to one of low fertility and low mortality (typical of modern industrialized countries). Even more directly relevant is the epidemiologic transition, first described by Omran¹: the shift from a pattern of high prevalence of infectious diseases associated with malnutrition, and periodic famine and poor environmental sanitation, to a pattern of high prevalence of chronic and degenerative diseases associated with urban-industrial life styles. A third pattern of delayed degenerative diseases has been more recently formulated (e.g., Olshansky and Ault²). Accompanying this progression is a major shift in age-specific mortality patterns and a consequent increase in life expectancy. Interpretations of the demographic and epidemiologic transition share a focus with the nutrition transition on the ways in which populations move from one pattern to the next.

Similarly, large shifts have occurred in dietary and physical activity and inactivity patterns. These changes are reflected in nutritional outcomes, such as changes in average stature and body composition. Modern societies seem to be converging on a pattern of diet high in saturated fat, sugar, and refined foods and low in fiber, often termed the "Western diet." Many see this dietary pattern to be associated with high levels of chronic and degenerative diseases and with reduced disability-free time. These three relationships are presented in Figure 1. (Download Figs 1 & 2 as PowerPoint slides)

Human diet and activity patterns and nutritional status have undergone a sequence of major shifts, defined as broad patterns of food use and their corresponding nutrition-related diseases. Over the last three centuries, the pace of dietary and activity change appears to have accelerated, to varying degrees in different regions of the world. Further, dietary and activity changes are paralleled by major changes in health status, as well as by major demographic and socioeconomic changes. Obesity emerges early in these shifting conditions as does the level and age composition of morbidity and mortality. We can think of five broad nutrition patterns. They are not restricted to particular periods of human history. For convenience, the patterns are outlined as historical developments; however, "earlier" patterns are not restricted to the periods in which they first arose, but continue to characterize certain geographic and socioeconomic subpopulations.

Pattern 1: Collecting Food

This diet, which characterizes hunter-gatherer populations, is high in carbohydrates and fiber and low in fat, especially saturated fat^3,4. The proportion of polyunsaturated fat in meat from wild animals is significantly higher than in meat from modern domesticated animals⁵. Activity patterns are very high and little obesity is found among hunter-gatherer societies. It is important to note that much of the research on hunter-gatherers is based on modern hunter-gatherers as there is much less evidence on pre-historic people.

Pattern 2: Famine

The diet becomes much less varied and subject to larger variations and periods of acute scarcity of food. These dietary changes are hypothesized to be associated with nutritional stress and a reduction in stature (estimated by some at about 4 inches^6,7. During the later phases of this pattern, social stratification intensifies, and dietary variation increases according to gender and social status⁸. The pattern of famine (as with each of the patterns) has varied over time and space. Some civilizations are more successful than others in alleviating famine and chronic hunger, at least for their more privileged citizens⁹. The types of physical activities changed but there was little change in activity levels during this period.

Pattern 3: Receding Famine

The consumption of fruits, vegetables, and animal protein increases, and starchy staples become less important in the diet. Many earlier civilizations made great progress in reducing chronic hunger and famines, but only in the last third of the last millennium have these changes become widespread, leading to marked shifts in diet. However, famines continued well into the eighteenth century in portions of Europe and remain common in some regions of the world. Activity patterns start to shift and inactivity and leisure become part of the lives of more people.

Pattern 4: Nutrition-related Noncommunicable Disease (NR-NCD)

A diet high in total fat, cholesterol, sugar, and other refined carbohydrates and low in polyunsaturated fatty acids and fiber, and often accompanied by an increasingly sedentary life, is characteristic of most high-income societies (and increasing portions of the population in low-income societies), resulting in increased prevalence of obesity and contributing to the degenerative diseases that characterize Omran's final epidemiologic stage.

Pattern 5: Behavioral Change

A new dietary pattern appears to be emerging as a result of changes in diet, evidently associated with the desire to prevent or delay degenerative diseases and prolong health. Whether these changes, instituted in some countries by consumers and in others also prodded by government policy, will constitute a large-scale transition in dietary structure and body composition remains to be seen^10-12. If such a new dietary pattern takes hold, it may be very important in enhancing "successful aging," that is, postponing infirmity and increasing the disability free life expectancy^13,14. Our focus is increasingly on patterns 3 to 5, in particular on the rapid shift in much of the world's low- and moderate-income countries from the stage of receding famine to NR-NCD. Figure 2 presents this focus. The concern about this period is so great that the term the Nutrition Transition is synonymous for many, with this shift from Pattern 3 to 4.

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References

1. Omran, Abdel R. 1971. "The epidemiologic transition: A theory of the epidemiology of population change," Milbank Quarterly. 49: 50938.
2. Olshansky SJ, Ault AB. 1986. "The fourth stage of the epidemiologic transition: The age of delayed degenerative diseases," Milbank Quarterly. 1986; 64: 35590.
3. Truswell AS. "Diet and nutrition of hunter-gathers." Health and Diseases in Tribal Societies. Ciba Foundation Symposium 149. Amsterdam: Elsevier. 1977; 21326.
4. Harris DR. "The prehistory of human subsistence: a speculative outline." In DN Walcher and N Kretchmer (eds.), Food, Nutrition and Evolution: Food as an Environmental Factor in the Genesis of Human Variability. New York: Masson. 1981; 1537.
5. Eaton SB, Shostak M, Konner M. The Paleolithic Prescription: A Program of Diet and Exercise and a Design for Living. New York: Harper & Row. 1988.
6. Eaton SB, Konner M. "Paleolithic nutrition: A consideration on its nature and current implications," The New England Journal of Medicine. 1985; 312: 2839.
7. Vargas LA. "Old and new transitions and nutrition in Mexico." In AC Swedlund and GJ Armelagos (eds.), Disease in Populations in Transition. Westport, CT: Greenwood. 1990.
8. Gordon KD. "Evolutionary perspectives on human diet." In FE Johnson (ed.), Nutritional Anthropology. New York: Liss. 1987; 341.
9. Newman L, Kates RW, Matthews R, Millman S. Hunger in History. Cambridge, MA: Basil Blackwell Ltd. 1990.
10. Milio N. Nutrition Policy for Food-Rich Countries: A Strategic Analysis. Baltimore: The Johns Hopkins University Press. 1990.
11. Popkin BM, Haines PS, Reidy KC. "Food consumption of U.S. women: Patterns and determinants between 1977 and 1985," American Journal of Clinical Nutrition. 1989; 49: 130719.
12. Popkin BM, Haines PS, Patterson R. "Dietary changes among older Americans, 1977-87," American Journal of Clinical Nutrition. 1992a; 55: 82330.
13. Manton KG, Soldo BJ. "Dynamics of health changes in the oldest old: New perspectives and evidence," Health and Society. 1985; 63: 20685.
14. Crimmins EM, Saito Y, Ingegneri D. "Changes in life expectancy and disability-free life expectancy in the United States," Population and Development Review. 1989; 15: 23567.