Undernourishment is a critical public health issue directly impeding the achievement of Sustainable Development Goal 2.1. Inadequate nutrition leads to severe health consequences, such as weakened immune systems, increased susceptibility to diseases, and stunted development in children. This condition predominantly affects low- and middle-income countries with growing populations, economic burdens, and inequalities in healthcare utilization. With this background, the objectives of this study are: first, to examine the current trends and the convergence hypothesis of undernourishment rates across low and middle-income countries second, to study the role of socioeconomic, climate change, agricultural productivity, and political factors on undernourishment third, to utilize predictive models to forecast the prevalence of undernourishment through different scenarios such as climate change, changing food systems, and political stability fourth, to assess the protein intake and affordability of a healthy diet and its impact on undernourishment and  finally, to investigate the effect of nutrition-sensitive aid on undernourishment. Data will be extracted from various secondary sources, such as Food and Agricultural Organizations, World Development Indicators, World Governance Indicators, and Organizations for Economic Cooperation and Development. Several econometrics techniques will be used for the empirical analysis. The study's findings will be relevant to the national health policy and contribute significantly to a comprehensive and equitable approach to address undernourishment issues at the national and international level.