Mapping Urbanization and Nutritional Outcomes

Urbanization in Nigeria associated with lower rates of child stunting but higher rates of obesity among women.

Urbanization is changing the landscape of health and nutrition in Africa, and in Nigeria, it relates to both lower levels of stunting among children and higher rates of obesity among women, according to two recent studies that used satellite-measured nighttime light intensity as a proxy for urbanization.

Fig 1 Night light intensity for both years, 2008 and 2013 (Source: Amare and Abay 2018) 

The Urbanization and Child Nutrition Outcomes was published in The World Bank Review, authored by IFPRI’s Mulubrhan AmareChanning Arndt, and Todd Benson along with Kibrom Abay of ILRI. Another related study on the Night Light Intensity and Women’s Body Weight: Evidence from Nigeria was published in Economics and Human Biology, authored by Amare and Abay. Both studies evaluated data of children five years or under and women of childbearing age (15-49) from Nigeria’s Demographic and Health Survey during 2008 and 2013.

The implications of urbanization on child nutritional outcomes are investigated using satellite-based nighttime light intensity data as a marker of urbanization with data from two rounds of the Nigeria Demographic and Health Survey. Nighttime light introduces a gradient of urbanization permitting investigation of the implications of urbanization on child nutritional outcomes along an urbanization continuum. Nightlight is found to significantly predict child nutritional outcomes even after controlling for observable covariates known to influence child nutrition. In all specifications, improvements in child nutrition outcomes onset with relatively low levels of light emissions and continue rapidly as nightlight intensity increases before largely leveling off. These nonlinear relationships highlight the value of nightlight as a population agglomeration indicator relative to traditional binary rural-urban indicators. Consistent with other recent work, patterns of urbanization influence welfare outcomes. At least for Nigeria, a pattern that extends the benefits of urban agglomeration to larger shares of the population would speed improvements to child nutritional outcomes.

Mulubrhan Amare, Channing Arndt, Kibrom A Abay, Todd Benson. 2018.  Urbanization and Child Nutritional Outcomes, The World Bank Economic Review.

The prevalence of overweight and obesity are increasing in many African countries and hence becoming regional public health challenges. We employ satellite-based night light intensity data as a proxy for urbanization to investigate the relationship between urbanization and women’s body weight. We use two rounds of the Demographic and Health Survey data from Nigeria. We employ both nonparametric and parametric estimation approaches that exploit both the cross-sectional and longitudinal variations in night light intensities. Our empirical analysis reveals nonlinear relationships between night light intensity and women’s body weight measures. Doubling the sample’s average level of night light intensity is associated with up to a ten percentage point increase in the probability of overweight. However, despite the generally positive relationship between night light intensity and women’s body weight, the strength of the relationship varies across the assorted stages of night light intensity. Early stages of night light intensity are not significantly associated with women’s body weight, while higher stages of nightlight intensities are associated with higher rates of overweight and obesity. Given that night lights are strong predictors of urbanization and related economic activities, our results hint at nonlinear relationships between various stages of urbanization and women’s body weight.

Abay, Kibrom A., and Mulubrhan Amare. “Night light intensity and women’s body weight: Evidence from Nigeria.” Economics & Human Biology 31 (2018): 238-248.