(October 2008) Chronic malnutrition has been a persistent problem for young children in sub-Saharan Africa. A high percentage of these children fail to reach the normal international standard height for their age; that is, they are "stunted." The region has now the world's highest rate of stunting among children—43 percent—and has shown little improvement over the past 15 years. In contrast, the percentage of children stunted in Southeast Asia dropped from 52 percent to 42 percent between 1990 and 2006.1

The number of undernourished (low weight for age) people of all ages in sub-Saharan Africa increased from about 90 million in 1970 to 225 million in 2008, and was projected to add another 100 million by 2015, even before the current world food price hikes.

Monitoring Progress Using Measures of Stunting

While the MDGs designated low weight for age as the indicator for measuring progress against malnutrition, a number of public health nutrition experts now prefer a more conceptually valid indicator, low height for age (or stunting), to measure longer-term deprivation of basic human needs. Moderately and severely stunted children (whose height-for-age ratios are two standard deviations below the international standard) have retarded physical growth and negative implications for child development, and school and work performance. The Demographic and Health Surveys (DHS), conducted worldwide by Macro International with support from the U.S. Agency for International Development (USAID), provide such standardized anthropometric indicators for 24 sub-Saharan countries for at least two points between 1986 and 2006.

There has been progress in some countries. One-quarter (six) of the 24 DHS country surveys with comparable population, health and nutrition levels in sub-Saharan Africa have shown important reductions in stunting among children under age 3 over these two decades, with declines of at least 2 percentage points per year. These six countries are Senegal, Namibia, Togo, Uganda, Eritrea, and Tanzania. Senegal has had the most dramatic reduction in stunting, from 22 percent in 1993 to only 14 percent in 2005. Another three countries (Botswana, Gabon, and Gambia) do not have DHS trend data, but the World Health Organization (WHO) and UNICEF indicate they already have low or moderate levels of stunting.2

However, the majority of sub-Saharan countries show no improvement in stunting since 1990 and/or have very high levels, with more than 40 percent of young children moderately and severely stunted. Of the 24 DHS trend data countries, five suffer from very high and/or deteriorating levels of stunting for children under age 3: Niger, Zambia, Malawi, Rwanda, and Madagascar.

Mapping the Highest Sub-Regional Stunting Patterns: The Sahel and Southeast Africa

The geographic distribution of stunting across the 41 sub-Saharan countries that have at least 1 million residents with reliable national trend or recent cross-sectional data reveals interesting patterns when depicted on a map. Two areas stand out as having high levels and stagnant or deteriorating trends: the Sahel (from Mali east to Chad) and southeastern Africa (from Rwanda and Zambia east to Mozambique and Madagascar). They are shown in dark orange on the map.

The other countries of concern, in yellow, have high stunting levels documented in recent national surveys, but do not have an earlier benchmark that could show a trend. Among the highest are countries that have experienced recent political and ethnic instability: the Democratic Republic of Congo, Sierra Leone, and Burundi.3


Levels and Trends in Childhood Stunting in Sub-Saharan Africa

Levels and Trends in Childhood Stunting in Sub-Saharan Africa 

Note: Countries in green have significant improvement, even though some may still have high levels of stunting.
Sources: Rates based on information from Demographic and Health Surveys (www.measuredhs.com); UNICEF Multiple Indicator Cluster Surveys (www.childinfo.org); and World Health Organization, Global Child Growth and Malnutrition Data Base (www.who.int/nutgrowthdb/en/).


The map demonstrates that on a regional basis, stunting has remained relatively low in most of southern Africa (especially Namibia, Botswana, and South Africa). Stunting has declined in the last 20 years (from 46 percent to 35 percent) in eastern Africa, demonstrated by improvement in Ethiopia, Uganda, and Tanzania, while it has worsened or stagnated in western Africa, the Sahel, and southeastern Africa.

What Accounts for Differences?

Why have some countries been able to improve their childhood nutrition between the 1980s and 2007 while others have not? Research has shown that nutrition is usually influenced by five interrelated factors: political instability; poverty/inequality; ineffective development policy; climate and environmental change; and inadequate and poorly administered food security, health prevention, and nutrition programs. Many of the countries with high or stagnant stunting levels are among the most fragile politically, having suffered recent wars and internal conflicts; these include the Democratic Republic of the Congo, Sierra Leone, and Somalia.

  • Household access to food, determined by access to land, off-farm labor, purchasing power, and intrahousehold resource allocation.
  • The household's capacity to access and use adequate health care and nutrition and child care for young children (including exclusive breastfeeding, weaning foods, and preventive care.
  • Illness or environmental health conditions (such as malabsorption of food) that affects the biological utilization of food.4

Aside from the geographic, demographic, political, and macroeconomic factors within each country, there are significant disparities in stunting between the urban and more-educated mothers, and the rural and less-educated mothers.5 The latter group are often twice as likely to have stunted children under age 3. Moreover, the disparities between rural and urban areas, and between urban slums and nonslums, are growing.

Demographic Factors Complicate Efforts to Reduce Stunting

Several demographic trends in sub-Saharan Africa may hinder efforts to reduce the chronic malnutrition among children. First is continued rapid rate of population growth, especially in most countries with high or stagnant rates of stunting, with the exception of Senegal and Uganda. Within a country, the poor—who are more likely to be malnourished—tend to have much higher fertility than the nonpoor; this disproportionately increases the size of higher risk populations. The additional population also exerts greater pressure on shrinking arable agricultural land and contributes to ecological degradation in the rain-fed agricultural, semiarid, and nomadic pasture areas in such countries as Rwanda and Ethiopia.

Two other trends in the region—rapid urbanization and changing consumption patterns—mean greater demand for agricultural products by people who often do not produce it. As a result, the poor in some urban areas, such as Nairobi slums, have worse nutrition than the poor in the rural areas.

The Way Forward: Addressing Stagnation in Stunting

For sub-Saharan countries to formulate and implement more effective policies and programs to reduce high and stagnant child stunting, they need to be able to reliably measure change, and to evaluate which policies and programs are effective. This requires advancements in four areas:

  • Methodology: More time series data are needed on the most unstable and fragile countries, and in the most vulnerable areas and seasons; stunting should be the indicator of choice when monitoring longer-term poverty and hunger reduction; and ongoing food security and nutrition surveillance and information systems will provide more targeted and contextual stunting-related data at household, agro-ecological, and program levels for policymaking.
  • Policy: Multisectoral policies that take holistic approaches that are well-implemented are more likely to reduce chronic malnutrition. The policies would target poverty reduction, food security, education, gender, disease burden, and population. International assistance for chronic stunting should not be interrupted for short-term emergency food aid (which targets the acutely malnourished), and should focus on prevention.6
  • Programs: Local capacity-building for policy and planning, and for assessing, monitoring and evaluating progress in meeting a country's own goals (preferable to the MDG goals) in reducing hunger and malnutrition, is essential. Development-oriented and preventive programs in food production, land tenure, jobs, education, gender, health care and water are more important in the long run than are direct feeding programs.7
  • Case study research and evaluation: Case studies and contextual analysis of the more successful countries in reducing stunting can provide valuable guidelines for future policy and program work. Support from USAID, UNICEF, FAO, World Bank, and other major funders and advisers could allow researchers to evaluate, for example, why Senegal has been so successful in reducing stunting in the last 10 years (by 36 percent), while the levels deteriorated by 31 percent in neighboring Guinea; why stunting increased at the same time that child mortality decreased dramatically in Zambia and Malawi;8 or how some countries (for example, Ethiopia and Eritrea) in the drought-prone Greater Horn of Africa succeeded in reducing stunting in the face of political instability and famine, while Kenya’s progress has stagnated since 1989.

Policymakers can learn more on progress in monitoring the MDG poverty goals of child stunting from reliable and comparative health and nutrition surveys, such as the USAID-supported DHS, and the UNICEF-supported Multiple Indicator Cluster Surveys.9 Program planners and evaluators in particular need to know not only which countries are progressing, but the location, number, process, and causes of chronic stunting within each country. They can do so even better from locally owned integrated food and nutrition surveillance systems that have knowledge of the contexts, risks, and vulnerabilities, as well as the resilience and capabilities in their areas.

Note: This article draws from research by the co-authors with Eckhard Kleinau and Kathy Rowan. See Charles Teller et al., 2007, and Soumya Alva et al., 2008, cited below. You are invited to send your comments to: cteller@prb.org.


Charles H. Teller is a Bixby Visiting Scholar at the Population Reference Bureau. Soumya Alva is a senior public health analyst with the Demographic and Health Research Group at Macro International.


References

  1. Food and Agriculture Organization (FAO), "Soaring Food Prices: Facts, Perspectives, Impacts and Actions Required," background paper prepared for the High-Level Conference on World Food Security: The Challenges of Climate Change and Bioenergy, Rome, June 3-5, 2008, accessed online at www.fao.org/foodclimate/conference/en/, on Sept. 15, 2008.
  2. World Health Organization (WHO), World Health Statistics, Child Growth and Nutrition Data Base, accessed online at www.who.int, on Aug. 11, 2008.
  3. Macro International, information based on Demographic and Health Survey data, acccessed online at www.measuredhs.com, on Aug. 11, 2008; and UNICEF/Childinfo, Multiple Indicator Cluster Surveys/MICS 3, country reports, accessed online at www.childinfo.org/mics3, on Sept. 15, 2008.
  4. Robert Black et al., "Maternal and Child Undernutrition: Global and Regional Exposure and Health Consequences," The Lancet 371, no. 9608 (2008): 243-60.
  5. Charles Teller et al., "Five Emerging Patterns of Demographic, Health and Nutrition Transitions and Stalls in Africa, 1986-2006," report prepared for USAID, August 2007.
  6. Marie Ruel et al., "Age-Based Preventive Targeting of Food Assistance and Behavior Change for Reduction of Child Undernutrition in Haiti: A Clustered Randomized Trial,"The Lancet 371, no. 9612 (2008): 588-95; Macro International, information based on Demographic and Health Survey data; and UNICEF/Childinfo, Multiple Indicator Cluster Surveys/MICS 3, country reports.
  7. Malawi, National Nutrition Policy and Strategic Plan, 2008-2011 (Lilongwe, Malawi: Office of the President and Cabinet, Dept. of Nutrition, June 2008).
  8. Soumya Alva et al., "A Growing Gap Between Malnutrition and Mortality Among Children in Sub-Saharan Africa," paper presented at the annual meeting of the Population Association of America, New Orleans, April 19, 2008.
  9. For additional examples, see Teller et al., "Five Emerging Patterns of Demographic and Health Transitions and Stalls"; and Alva et al., "A Growing Gap Between Malnutrition and Mortality."