Abstract:

Access to a healthy diet is a fundamental human need, yet large parts of the global population remain unable to afford it. Conventional poverty metrics rely on observed food consumption by low-income people scaled to caloric requirements and therefore fail to capture the full cost of meeting nutritional needs. In Stehl et al. 2025, we proposed poverty lines based on the cost of a healthy diet, incorporating elements of relative poverty. Here, we update these estimates using newly compiled data through 2024 and an expanded dataset on food expenditure shares that captures temporal variation in household consumption allocations. Incorporating time-varying expenditure shares reduces biases arising from static assumptions on consumption structure and improves cross-country comparability. Compared to conventional international poverty lines, these estimates identify around four times more individuals as poor. They also highlight the scale of global undernutrition risk when dietary guidance rather than caloric sufficiency is used as the benchmark for basic needs.

About the presenter:

Dr Jonas Stehl is a postdoctoral researcher at the University of Göttingen, member of the Research Training Group 2654 Sustainable Food Systems and the Chair of Development Economics and Global Health. Currently visiting Harvard T.H. Chan School of Public Health.

His work focuses on food security and poverty, primarily in low- and middle-income countries. Drawing on large cross-country and geospatial data, Stehl studies dietary patterns around the globe, focusing on the affordability of nutritious foods and the role of self-sufficiency and market dependencies at both micro and macro levels. Stehl also investigates the long-term persistence of these patterns. Additionally, he examine the conceptual foundations of poverty and investigate whether labor market programs can effectively alleviate it.

In his research, he uses descriptive, experimental, quasi-experimental, and machine learning techniques.

Stehl's research has been supported by the German Research Foundation (DFG), the European Centre for Advanced Studies (ECAS), and the Joachim-Herz Foundation.