Beyond Calories: Addressing Micronutrient Deficiencies in the World’s Most Vulnerable Communities—A Review

Micronutrient deficiencies, also known as "hidden hunger," remain a pervasive public health issue in low- and middle-income countries, particularly among vulnerable populations within these countries. The main drivers of these deficiencies are poverty, limited dietary diversity, weak nutritional strategies, poor health service delivery and general health access barriers. This review assesses the prevalence, drivers, and consequences of selected micronutrient deficiencies: iron, iodine, zinc, vitamin A and vitamin D, within the scope of undernutrition, food insecurity, and socioeconomic inequity. The consequences associated with these deficiencies include stunted growth, increased susceptibility to illness, poor cognitive and social functioning, and deepened poverty. The primary strategies to address these deficiencies include dietary diversification, supplement provision, biofortification, and the production of fortified foods. Barriers to progress include the high cost of food, weak healthcare infrastructure, low educational levels, and ineffective policy implementation. Integrated food systems, personalised nutrition, and innovative food technologies have the potential to address both nutritional and health inequities. Addressing barriers to safe and nutritious food and healthcare systems in order to address health inequities requires integrated, multisectoral planning and contextual policy. Improving individual health outcomes is crucial, but addressing micronutrient deficiencies has a ripple effect throughout society, enabling economic development through poverty reduction and increased productivity.