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Nutrition and urbanization
Nutrition and urbanization: Introduction
Health services and environmental factors in urban slums and shanty towns of the developing world
Trends in urban and rural food consumption and implications for food policies in Tunisia
Nutrition-related health consequences of urbanization
Urbanization and hunger in the cities
Nutrition and urbanization: Introduction
A rapid demographic transition has been occurring in a number of low-income countries: there has been a major shift of the rural poor toward the cities. The Sub-committee on Nutrition of the United Nations Administrative Committee on Co-ordination is concerned with the potential repercussions of this phenomenon. The policies currently pursued by many low-income countries, combined with difficult economic conditions, may lead to a deterioration in the quality of life of the urban poor, i.e., those who have low incomes or are unemployed. This issue of the Food and Nutrition Bulletin and the next one deal with nutrition problems that may result from neglect of this population, whose members often differ nutritionally in important ways from either the rural poor or the "average'' urban dweller.
The papers in these two special issues attempt to answer questions such as: What are the universal dimensions of the nutrition problems of this group? What are its major social characteristics? Is the nutritional status of urban dwellers better or worse than the status of those who live in rural environments? How are mothers and children affected? Are there effective programmes to satisfy the food consumption needs of the urban poor?
The data on poor urban dwellers are scant. Urban and rural differences are often not documented and even when they are, it is frequently impossible to disaggregate the data by income level. It may not be possible, therefore, to ascertain how much worse off the urban poor are than either their rural counterparts or the average urban dweller.
There are a number of factors associated with urban residence that have positive and negative nutritional consequences for the low-income population. Factors with positive effects include diversity in available food, greater mobility, better opportunities for employment and education, and lower expenditure of food energy. Factors with a negative impact include a cash economy in which most foods have to be purchased, crowding, less extended-family interaction, and a higher probability of social maladjustment. It must be remembered, however, that many of the urban poor are migrants and that migrants differ from non-migrants in their willingness and ability to take a chance in a new place in an attempt to improve their life. They have to adjust and adapt. The differences between the rural and urban poor, therefore, may not be due solely to the stresses of urban living but also to other predetermined differences.
The papers in these two issues draw attention to the gravity of urban malnutrition in the third world. An obvious conclusion is that it is not possible to isolate nutrition problems by dissociating them from all others. A holistic view is necessary. The analyses presented recognize the multidimensionality of the situation. Viteri elaborates on the specific nutrition problems accompanying urbanization. Rossi-Espagnet concentrates on health in general and, within this area, on the broad nutritional aspects. Lunven and Hussain examine hunger in the cities and suggest measures to combat it. A case study of food consumption in Tunisia is presented by Périssé and Kamoun.
In the next issue of the Bulletin, Popkin and Bisgrove will provide an overview of urbanization in a broad perspective; Reutlinger will present a theoretical model of the nature and function of food subsidies and outline a cost-effective scheme to supplement the purchasing power of the urban poor; and Musgrove will present a case study on food consumption in north-east Brazil.
There is agreement among the contributors that diets are more diversified in urban areas and that the purchasing power of the urban poor needs to be increased in order to improve their nutrition. There is also agreement that total food-energy consumption in urban areas is less than in rural ones; there is no consensus, however, on whether this reduction results in energy deficiencies or is itself the result of decreased needs. Viteri, for example, states that protein-energy deficiency is less prevalent in urban than in rural areas, while Musgrove argues that the tendency to improve the quality of diet at the expense of quantity makes the urban population more susceptible to undernutrition. Musgrove believes that the nutrients per unit of energy may be better in the cities than in rural areas but that the total quantity of energy consumed is likely to be less adequate. There is also no consensus on the prevalence of infection and its potential effects on growth and development.
Regarding the implications of urbanization for pregnant and lactating women and preschool-aged children-who constitute particularly vulnerable groups -the following conclusions can be drawn:
1. More women are employed outside the home and there are more
female-headed households in urban areas. These employment and
household patterns have health-related repercussions. An example
is that more food is purchased from vendors, which may be less
hygienic and less nutritious than home-cooked food. As the
workload of women increases, there is often more child neglect
and less opportunity to rest during periods of pregnancy and
2. There is a decline in breast-feeding, which may have lifelong repercussions in terms of growth and development and protection from infection.
3. The incidence of low birthweight, infant mortality, anaemia, and general malnutrition is very high in periurban slums and shanty towns.
4. In urban areas more children may be employed than elsewhere, but more of them live on the streets. The malnourished Oliver Twists of the last century are barely surviving today in many metropolises of the third world.
Urbanization has been viewed positively for industrialized countries but is seen negatively now for third-world ones. One reason may be that the number of urban dwellers, especially in the third world, is predicted to be enormous by the year 2000 (see table 2 in Viteri in this issue). Some of this increase is attributed to migration as rural populations raise their economic and social expectations, and some to high birth rates. The population pyramid also shifts toward a greater number of elderly in urban areas.
While rural labour productivity does not appear to suffer as a consequence of urbanization because rural dwellers who were previously unemployed replace those who migrate to the cities, the loss of fertile agricultural land to urban use is significant for farming areas close to cities. Hussain and Lunven estimate that this loss will reach ten million hectares globally betwen the years 1980 and 2000. The process of urbanization in the third world is not confined to capital cities. As Rossi-Espagnet points out in this issue, this phenomenon does not appear to be temporary. It is different from that which took place in Europe, where industrialization preceded urbanization; today industrial growth generates fewer employment opportunities. It is not known with any certainty whether the process of urbanization is inevitable and what its long-term repercussions may be.
The following general points regarding the positive and negative effects of urbanization on the nutrition of the poor emerge from the papers in these two issues:
1. Weaning and complementary-feeding practices are better in urban areas because of the greater availability and promotion of weaning foods.
2. Fewer urban children have growth problems after early infancy, because of better diets and lower infection rates.
3. In addition to some food that gets from the rural to the urban areas through extended families, more importantly, there are remittances that flow from urban to rural areas to help improve farming methods.
4. The quality of food is better in urban areas because of increased variety, larger price elasticities, and greater substitution effects. These factors have both positive and negative consequences. On the positive side, even low-income populations consume a more varied diet then their rural counterparts, which leads to increased intakes of certain nutrients and improved absorption of others. On the negative side, there is a greater intake of nutritionally poor foods such as soft drinks, commercially baked goods, fried snacks, and sweets.
5. Urban populations have to purchase all or most of their food. In Tunisia the minimum acceptable level of income for adequate nutrition is 100% higher in urban than in rural areas (see table 5 in Périssé and Kamoun in this issuer. The purchase of adequate food in urban areas may be prevented in part by expenses for transportation to and from work, as well as housing and utilities, which are often not concerns of rural households.
6. Many governments' current policies have adverse effects on urban nutrition, which undermine political stability. If governments, for example, were more responsive to short-term problems, it would be possible to avert much long-term dependency by urban residents.
7. While it is true that medical, social, and cultural services are better and more readily available in urban areas, it is also true that low-income populations do not necessarily have access to them.
8. Some conditions with nutrition-related consequences, such as alcoholism, drug addiction, rickets, and osteomalacia are more severe in urban centres than elsewhere. Other conditions that may result from environmental changes associated with urbanization are cancer and cardiovascular disease.
In conclusion, it is important to keep in mind that many of the data on urban dwellers are averages and do not accurately describe the plight of the poor who reside in slums and shanty towns. The major factors of environmental conditions, time constraints for women, and lack of purchasing power-all of which impact on nutritional status-are interactive and can only be tackled with multidisciplinary programmes that are sensitive to societal needs.
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