This article examines the contemporary methodologies and effectiveness of food security measurement tools developed by the Food and Agriculture Organization of the United Nations, with particular emphasis on the Food Insecurity Experience Scale, Global Food Security Index, and Integrated Food Security Phase Classification. Through analysis of global trends and measurement approaches, the research reveals that whilst global undernourishment decreased from 12% to 9.2% between 2004-06 and 2020-22, moderate to severe food insecurity increased from 21.9% to 29.5%. The study demonstrates significant regional variations, with Africa experiencing the highest prevalence of food insecurity (58.9%) and Europe maintaining the lowest levels (<2.5%). In India, despite a reduction in undernourishment from 21.4% to 16.6%, severe food insecurity increased markedly from 15.4% to 22.72%. The analysis identifies strengths and limitations of current measurement tools, noting FIES's cost-effectiveness but potential cultural bias, GFSI's comprehensive scope but reliance on secondary data, and IPC's multi-dimensional approach but resource-intensive implementation. The research concludes by proposing methodological improvements, including the integration of qualitative and quantitative data, enhanced localised assessments, and the incorporation of remote sensing technologies to strengthen the precision and reliability of food security measurements globally.