FSI

Most global food security assessments rely on subjective expert weights. These methods often miss the multidimensional nature of food systems, limit comparisons over time, and may underestimate governance. To address these issues, this study develops an objective, data-driven Food Security Index (FSI). We apply principal component analysis to eight indicators covering the four Food and Agrulture Organization (FAO) pillars for 122 countries from 2000 to 2021. Indicator weights are derived empirically rather than assigned by experts, and countries are grouped into four security tiers using k-means clustering. The first principal component explains 60.36% of the variance, with political stability and protein supply as the strongest contributors. Sub-Saharan Africa and South Asia are concentrated in low-security tiers despite diverse income levels, and several upper-middle-income countries underperform due to inequality and institutional fragility. The FSI shows strong convergent validity with the Global Food Security Index (ρ = 0.81), yet income alone is neither necessary nor sufficient for food security. Finally, governance quality and dietary adequacy anchor food security more than calorie availability. Policy priorities should be tailored by tier, with foundational infrastructure in low-security contexts, shock-resilience mechanisms in middle tiers, and targeted subnational interventions in high-security settings.