Micronutrient and Macronutrient Deficiencies: A Comprehensive Review of Scientific Literature

Abstract Nutritional deficiencies, involving both micronutrient and macronutrient inadequacies, continue to pose a significant public health challenge worldwide, particularly in low- and middle-income countries. This comprehensive literature review synthesizes current scientific evidence on the prevalence, causes, health consequences, and intervention strategies related to nutritional deficiencies. Key micronutrient deficiencies such as iron, vitamin A, iodine, and zinc are examined alongside macronutrient deficits including protein-energy malnutrition. The review highlights multifactorial causes, including inadequate dietary intake, infectious diseases, and socioeconomic factors. Effective prevention and intervention approaches—such as dietary diversification, supplementation, food fortification, and addressing social determinants—are discussed. The findings underscore the necessity of integrated, multisectoral strategies and sustained political commitment to reduce the global burden of malnutrition. This paper provides a critical resource for researchers, policymakers, and practitioners aiming to enhance nutrition outcomes and promote health equity. Keywords Nutritional deficiency, micronutrients, macronutrients, malnutrition, supplementation, food fortification, dietary diversity, public health, malnutrition interventions