For the first time in history, more than half of the world’s population lives in cities. This figure is expected to rise to 68 percent by 2050, presenting a host of new challenges and opportunities. The theme of this year’s World Cities Day (Oct. 31) is “Building Sustainable and Resilient Cities.” Sustainability and resilience are often defined in terms of cities’ capacity to adapt to rapidly-changing technological, environmental, and economic realities. Resilience also relates to the preparedness of cities to respond to global climate challenges and population growth. But what about the resilience of city dwellers?

The urban poor: Diet-related health and nutrition challenges

The explosive growth in cities on a global scale has generated economic opportunities, especially in low- and middle-income countries. At the same time, it has engendered unique challenges. Migration to cities from rural and peri-urban areas transforms living arrangements, family dynamics, work, and lifestyles. The urban poor in particular face unprecedented diet-related health and nutrition challenges. Malnutrition—and the policies to address it—has historically been associated with rural areas, but high rates of malnutrition are now plaguing the urban poor. This trend is often masked by data aggregated at the national or city level; rates of childhood undernutrition among the urban poor often rival those of the rural poor.

The urban poor face unique nutrition challenges. Unhealthy diets are at the root of all forms of malnutrition, including undernutrition and deficiencies of essential micronutrients and problems of overweight, obesity, and diet-related non-communicable diseases (NCDs) such as diabetes, cardiovascular diseases, and certain types of cancer. City-dwellers in low- and middle-income countries are rapidly shifting away from traditional diets rich in coarse grains and pulses and towards diets high in refined sugar, saturated fats, animal-sourced foods, and processed and ultra-processed foods. While this nutrition transition is happening everywhere, it is unfolding at a much faster pace in urban areas of low- and middle-income countries.

Three levels of factors affect food choices, contributing to these worrying trends: Consumer characteristics (including sociodemographic and economic status, age, gender, taste and preferences) and choices; the food environments around consumers (quality and types of foods, food stores or markets, and restaurants; the price of food; the quality, safety, and/or taste of available foods; and the advertising and marketing of different types of food products); and food systems (all activities involving the production, processing, transport and consumption of food).

One factor driving problematic nutrition trends among the urban poor is the rapid spread of supermarkets in the cities of low- and middle-income countries. Supermarkets potentially provide year-round access to a variety of fresh fruits and vegetables and refrigerated (safer) meat, fish, and dairy products to those who can afford them. But supermarkets also sell a large variety of convenient and cheap, ready-to-eat, and often highly-processed foods with high caloric, fat, sugar, and salt content, but low concentrations of protein and essential micronutrients which contribute to rising rates of overweight, obesity, and NCDs.

The diets of the urban poor are influenced by employment, income, and the affordability of food—but also by several unique aspects of urban life. While the poor in rural areas often produce much of their own food, time- economic- and infrastructure constraints force the urban poor to purchase most of the food they consume. A large proportion of the urban poor, including women, work outside the home, often in poorly paid, informal sector jobs. They live in precarious temporary housing, without rights to their residences and without proper infrastructure like electricity, cooking facilities, safe water, or decent sanitation facilities. As a result, poor urban dwellers often rely on convenient, ready-to-eat foods, prepared meals, or food and meals purchased from street vendors, which may not be nutritious or safe. Urban residents are also more likely to use motorized transport and to have sedentary jobs, decreasing their levels of physical activity.

This, combined with diets excessively high in calories, increases their risks of overweight, obesity, and NCDs; in addition, the consumption of foods prepared and stored in unsanitary conditions in informal markets or in the streets raises concerns of foodborne diseases—adding more risk to the nutrition and health burden of the urban poor.

Looking ahead: The human dimensions of sustainability and resilience

Global leaders are today recognizing that economic growth alone cannot solve the compounded diet, nutrition, and health problems the urban poor face. The resilience of urban populations depends on addressing these new and pressing nutrition challenges. The first step towards accomplishing this task is an innovative research agenda focused on strengthening and leveraging food systems and food environments to improve the access of poor urban populations to nutritious diets, health, and nutrition.

IFPRI is currently developing a research program on urban food systems, diets, and nutrition to address these challenges head-on, and to guide policy makers and other key actors in designing and implementing effective food systems policies to support healthier diets and optimal nutrition and health for the urban poor. As a leader in food policy research, with regional, national, and global networks and partnerships, IFPRI is uniquely suited to spearhead this comprehensive, multi-country research program. It has two primary areas of focus:

1. Poor urban consumers and the food environment. Researchers will generate evidence on the diets, nutrition, and health of poor urban dwellers and how the urban food environment shapes these outcomes; they will investigate how food environments can be reshaped to support the urban poor in achieving healthy diets and optimal nutrition and health.
2. Urban food systems. The program will develop the knowledge and tools needed to identify policies and investments that will foster healthy urban food systems that achieve the dual goals of improving the diets of the urban poor and contributing to rural transformation.

To be successful in “Building Sustainable and Resilient Cities” in a rapidly urbanizing world, policy makers, governments, civil society, and the international community at large must not only consider the technological and infrastructural aspects of urban areas, but also their unique human dimensions, most critically as these relate to the urban poor and the problems they confront daily.

Marie Ruel is Director of IFPRI’s Poverty, Health, and Nutrition Division (PHND); Jef Leroy is a PHND Senior Research Fellow; Elisabeth Becker is a PHND Senior Research Assistant.