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Malnutrition is one of the world’s most serious but least-addressed development challenges. Its human and economic costs are enormous, falling hardest on the poor, women, and children. In 2020, 149 million children under five years old were stunted (low height-for-age), which indicates not only a failure to achieve one’s own genetic potential for height but is also a predictor of many other developmental constraints, including cognitive deficits and future economic opportunities, including impeding a country’s ability to accumulate human capital.

Over the last three decades, the worldwide prevalence of stunting declined from 40 percent in 1990, to 22 percent in 2020. However, the health and food systems disruptions caused by the COVID-19 Pandemic has rolled back years of progress on child undernutrition; it is estimated that, by 2022, an additional 9.3 million children will suffer from acute malnutrition and 2.6 million more children will be stunted. Additionally, stark regional differences in the current prevalence and numbers of stunted children persist, with South Asia and Sub-Saharan Africa remaining above the global averages. Almost 31 percent of all children under five were stunted in South Asia in 2020, decreasing from approximately 60 percent in 1990. Even though the prevalence of child stunting in Sub-Saharan Africa fell from 48 percent in 1990 to 32 percent in 2020, the total number of stunted children in Africa increased by 13.1 million during the same period as a result of high fertility rates and lower rates of decline in stunting.

Stunting early in a child’s life can cause irreversible damage to cognitive development and has educational, income, and productivity consequences that reach far into adulthood. The economic costs of undernutrition, in terms of lost national productivity and economic growth, are significant— our economy and society is paying US$3 trillion a year in the form of productivity loss, ranging from 3 to 16% (or more) of GDP in low-income settings. Moreover, the global expert consortium, including the World Bank, estimated economic productivity losses equivalent to US$29 billion globally by 2022 as a result of the additional malnutrition burdens attributable to the COVID-19 pandemic.

Fortunately, these losses are largely preventable if adequate investments in proven interventions are made, particularly those that focus on ensuring optimal nutrition in the critical 1000-day window between the start of a woman’s pregnancy and her child’s second birthday. 

Globally, undernutrition is more common in poor households, but is also prevalent among wealthier households. Income is one—but not the only—determinant of stunting: food insecurity, diets lacking in diversity, high rates of infectious diseases and inappropriate infant feeding and care practices, and poor sanitation and hygiene practices also contribute to persistent stunting. Food and financial crises, as well as conflict, natural disasters and the COVID-19 Pandemic, have worsened undernutrition in many regions.

At the same time, a global nutrition transition is underway, leading to rapid changes in food systems, environments, and living conditions in many low- and middle-income countries (LMICs). These changes have stimulated a rapid increase in the burden of overweight and obesity, previously considered an ailment of wealthy countries. In fact, over the past 30 years, rates of overweight have risen faster in LMICs than in high income countries, and every region has seen some increase in the prevalence in overweight children under five years. In 2020, 38.9 million children under 5 were affected by overweight and obesity, which are now pervasive even in countries where children experience undernutrition. Overall, it is estimated that overweight and obesity cost US$2 trillion in economic and social expenses globally.

Countries are therefore starting to experience the double burden of overweight and stunting. Today, more of the world’s overweight individuals reside in low- and middle-income countries than in high income countries, and there is no evidence that the rise in obesity in LMICs will decline. As countries experience economic growth and achieve middle and upper-middle income status, their poor will experience a greater share of the burden of overweight and obesity, increasing their vulnerability to health and economic shocks. Both obesity and undernutrition are critical to improving human capital, a central driver of sustainable growth and poverty reduction, and can have a significant effect on the human capital index (HCI). There is an urgent need to ensure that the world’s poor have access to the knowledge, resources, and services needed to achieve optimum nutrition.



INFOGRAPHIC: Human Capital Index: The Story

INFOGRAPHIC: Global Nutrition Report

Last Updated: Sep 28, 2021

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