Unraveling Tanzania’s Breadbasket paradox in child nutrition

Tanzania's "Breadbasket Regions (BBRs)" are the core of the country's food supply, contributing over 38% of Tanzania's national maize production. However, the 2018 National Nutrition Survey revealed a paradox: the five regions with the highest rates of child stunting and severe malnutrition in the country are all located within these high-agricultural-yield areas. This "breadbasket paradox" has raised concerns: why are children in major food-producing regions more prone to growth issues than those in non-food-producing regions?

Recently, Professor Xu Tian from the College of Economics and Management at China Agricultural University, in collaboration with Mosses Lufuke from the Department of Economics at the University of Dodoma in Tanzania, uncovered the underlying reasons through data analysis. The related article has been published in Frontiers of Agricultural Science and Engineering (DOI: 10.15302/J-FASE-2025645).
The research team utilized comprehensive data from Tanzania's 2017-2018 National Household Budget Survey, 2020-2021 National Integrated Labor Force Survey, and 2020-2021 National Panel Survey, covering 7360 households, to analyze the relationship between crop production and children's growth status. Unlike previous studies that relied on descriptive statistics, this study employed Propensity Score Matching (PSM) and instrumental variable models, controlling for confounding factors such as household income, household size, and urban-rural differences, to verify the authenticity of the "breadbasket paradox" from a statistical perspective.

The results showed that the stunting rate among children in BBRs was significantly higher than that in non-BBRs. More importantly, there were regional differences in the impact of crop production on child nutrition: in non-BBRs, higher food production significantly reduced the risk of child stunting and improved height development; however, in BBRs, this positive effect was not significant - even with increased production, children's growth status did not improve accordingly.

To explore the causes of this paradox, the research team analyzed two potential mechanisms. The first was "maternal working hours": does higher production lead mothers to participate more in agricultural work, thereby reducing the time spent caring for children? Data showed that there was no significant correlation between crop production and mothers' out-of-home working hours in either BBRs or non-BBRs, so this hypothesis was not supported.

The second mechanism was "dietary diversity": does higher production result in a more monotonous household diet? The study found that in non-BBRs, increased food production did lead to greater household dietary diversity, which was directly related to improved nutrition; however, in BBRs, despite higher production, there was no significant increase in household dietary diversity. This may be related to the high degree of agricultural commercialization in BBRs - farmers tend to cultivate single cash crops for sale rather than growing a variety of foods for their own consumption, leading to the phenomenon of "high production but monotonous diet".

The study pointed out that simply increasing food production is insufficient to solve the problem of child malnutrition, especially in regions with a high degree of agricultural commercialization. Tanzania's current agricultural policies may overemphasize production increases while neglecting the key role of dietary diversity in children's growth. The study suggested that future policies could be adjusted in three aspects: first, encouraging farmers in BBRs to grow a variety of crops to balance economic benefits and household consumption; second, strengthening the construction of agricultural product markets to enable farmers to obtain income by selling cash crops to purchase a variety of foods; third, specifically improving the allocation of household resources, such as helping women reduce the burden of non-agricultural work like water-fetching, to ensure they have time to prepare nutritious food.