Nutrition transition
Nutrition transition is the shift in dietary consumption and energy expenditure that coincides with economic, demographic, and epidemiological changes. Specifically the term is used for the transition of developing countries from traditional diets high in cereal and fiber to more Western-pattern diets high in sugars, fat, and animal-source food.
Historical framework
The nutrition transition model was first proposed in 1993 by Barry Popkin, and is the most cited framework in literature regarding the nutrition transition, although it has been subject to some criticism for being overly simplified. Popkin posits that two other historic transitions affect and are affected by nutritional transition. The first is the demographic transition, whereby a pattern of high fertility and high mortality transforms to one of low fertility and low mortality. Secondly, an epidemiological transition occurs, wherein a shift from a pattern of high prevalence of infectious diseases associated with malnutrition, and with periodic famine and poor environmental sanitation, to a pattern of high prevalence of chronic and degenerative diseases associated with urban-industrial lifestyles is shown. These concurrent and dynamically influenced transitions share an emphasis on the ways in which populations move from one pattern to the next.Popkin used five broad patterns to help summarize the nutrition transition model. While these patterns largely appear chronological, it is important to note that they are not restricted to certain periods of human history and still characterize certain geographic and socioeconomic subpopulations. The first pattern is that of collecting food, a characterization of hunter-gatherers, whose diets were high in carbohydrates and low in fat, especially saturated fat. The second pattern is defined by famine, a marked scarcity and reduced variation of the food supply. The third pattern is one of receding famine. Fruits, vegetables, and animal protein consumption increases, and starchy staples become less important in the diet. The fourth pattern is one of degenerative diseases onset by a diet high in total fat, cholesterol, sugar, and other refined carbohydrates and low in polyunsaturated fatty acids and fiber. This pattern is often accompanied by an increasingly sedentary lifestyle. The fifth pattern, and most recently emerging pattern, is characterized by a behavioral change reflective of a desire to prevent or delay degenerative diseases. Recent and rapid changes seen in developing countries from the second and third pattern to the fourth is the common focus of nutrition transition research and desire for policy that would emphasize a healthier overall diet characterizes the shift from the fourth to the fifth pattern.
The nutritional transition, like the demographic and epidemiological transitions, shows a change in human dietary and activity patterns over time, affecting overall nutritional status. The nutritional transition argues that the previous periods in the transition continue in certain geographic and socio-economic subpopulations at different times.
Pattern 1: Collecting food
Hunter gatherer diet, high in carbohydrates and fibre, low in fat.
Activity patterns are very high with little obesity.
Pattern 2: Famine
Diet becomes less varied as people settle with periods of acute scarcity. Towards the end of this phase variation increases, but social stratification intensifies, with the most impoverished and women and children suffering the brunt of the burden of food scarcity.
Pattern 3: Receding Famine
Increase in animal proteins and fruits and vegetables. Activity patterns shift to include more leisure activities. Current climate changes are effecting movement out of the famine and receding famine period.
Pattern 4: Nutritional-related NCD
Diet becomes high in fat, cholesterol, sugar and other refined foods. This is accompanied by a continued shift to a sedentary lifestyle, which increases the prevalence of obesity and degenerative diseases. This matches on with the final phase of the epidemiological transition.
Pattern 5: Behaviour change
In response to the shifts happening in pattern 4, behaviours pushed by governments, the health system or individuals are expected to prevent or delay the degenerative diseases.
Relation to economic development
The nutrition transition has much of its roots in economic factors related to the development of a nation or subpopulations within a nation. It was once believed that current nutrition transition was endemic only to industrialized nations like the United States, but increasing research has indicated that not only is nutrition transition occurring most rapidly in low- and middle-income developing countries, the stress of its effects stands to burden the poorest populations of these countries the most as well.This shift is attributable to many causes. Globalization has played a large role in altering the access and availability of foods in formerly undeveloped nations. Demographic shifts from rural to urban areas are central to this as well as the liberalization of food markets, global food marketing, and the emergence of transnational food companies in developing countries. All these forces of globalization are creating lifestyle changes that contribute to the nutrition transition. Technological advancements are making previously arduous labor less difficult and thus altering energy expenditure that would have helped offset the caloric increases in the diet. Daily tasks and leisure are also affected by technological advancements and contributing to greater rates of inactivity. The aforementioned increases in calorie are due to increased consumption of edible oils, animal-source foods, caloric sweeteners, accompanied by reduced consumption of grains and fruits and vegetables. These changes play into human biological preferences seen across the world. Socioeconomic factors also play an important role as do cultural values tied to appearance and status.
Globalization and economic factors
The current nutrition transition seen in the emerging markets of Asia, Latin America, the Middle East, North Africa, and urban areas of sub-Saharan Africa is largely a product of globalization. International food trade, investment, commercialization and marketing are drastically impacting the availability of and access to energy-dense, but nutrient-deficient foods causing the aforementioned shift from traditional diet. Another byproduct of globalization has been a marked demographic transition in these countries from rural areas to urban ones. Urban populations are more susceptible to current trends in nutrition transition because of the improved transportation, commercial food distribution and marketing, less labor-intensive-occupations, and changes in household eating habits and structure.The liberalization of food markets has had a drastic effect on consumption patterns across the globe. Liberalization and commercialization of domestic agricultural markets are opening up food trading since this is needed to compete in the world market. This had led to changes in the types of food produced, and increases in amounts of food imported into developing countries, which affects the relative availability and prices of different foods.
Food demand is being shaped by increases in income and urbanization. As these rapidly developing nations continue to accrue high incomes per capita, their food spending is increasing as well. They elect to use these higher incomes on more calorically-dense foods that are sweeter and higher in fats. For example, in China, for the same extra dollar of income, an average Chinese person is purchasing higher calorie food today than that person would have done for the same extra yuan in 1990. Rapid urbanization has also shaped food demand globally. The demographic transition from rural areas to urban populations is a well documented byproduct of globalization and technological advancements. This is because agro-food systems have replaced local subsistence farming in many rural areas.
The supply of food is directly sculpted by increasing demand in these areas with growing income. Urbanization is increasing access to new foods and therefore altering the supply chain. This is why transnational food companies have grown so rapidly over the past few decades. These companies are making processed and fast foods much cheaper and more widely available through the growth of transnational supermarkets and chain restaurants. Food is not only easier to obtain in urban areas; it is also cheaper and less time-consuming to acquire which creates an imbalance between energy intake and output. Their advertising and promotional strategies have a strong effect on consumer choices and desire. Foreign direct investment is also stimulating processed food sales in these supermarkets by lowering prices and creating incentives for advertising and promotion. A large proportion of this advertising is for energy-dense processed foods and is being directed at children and youth.
Technological and transportation advancements are reducing the barriers that once limited global food trade. These techniques are critical to facilitating the production and distribution needed in a global market. Better preservation techniques are helping to reduce waste which contributes to lower prices for consumers. Technology is creating higher yields which also reduce prices.
Lifestyle changes
The forces of globalization are strongly influencing many lifestyle changes in developing countries. Major changes in economic structures from agrarian economies to industrialized economies are reducing physical activity levels in occupations around the world. Even in agricultural work, gas-powered technologies are helping reduce the energy expenditure needed to perform pertinent farming tasks. These reduced activity levels are not just seen in the workplace, but in homes as well. Daily tasks that were once laborious engagements are now much easier with the help of technological advancements, with examples being appliances such as washing machines, refrigerators, and stoves. Also, recent leaps in the efficiency of food production and improvements in cookware, such as the introduction of improved metal stoves which use fossil fuels and microwave ovens, have helped reduce domestic efforts greatly.Leisure is being greatly impacted as well. Activities such as playing sports outside are being replaced with television watching and computer games. Decreasing physical leisure activities can also be contributed to urbanization wherein access to fields needed to play such games as soccer are not available due to such dense populations and their subsequent demand for land. Other important lifestyle changes fueling the nutrition transition relate to the composition of diets. These dietary shifts have been mentioned previously several times but deserve greater scrutiny. Diets rich in legumes, other vegetables, and coarse grains are disappearing in all regions and countries. Taking their place are diets characterized by fat-rich edible and vegetable oils, cheap animal-source foods high in fat and protein, and artificially sweetened foods high in sugar and refined carbohydrates. Consumption of caloric beverages such as soda represented 21% of all calorie intake in Mexico from 1996 to 2002. Processes of globalization that have influenced food markets have made these products much cheaper, flavorful, and easier to produce which has in turn driven up their demand. So while globalization and the accompanying economic development has created higher levels of food security for developing countries, the ongoing trend of eating in a more Western fashion has caused increased rates of adverse health and childhood obesity.