The Interplay of Selenium and Human Health

Abstract

This chapter delves into the intriguing dual nature of selenium (Se), a vital yet paradoxical essential trace element for human health. While indispensable for numerous physiological processes, Se has an extremely narrow margin between its benefits and potential toxicity, making its intake a delicate balancing act. Still, its consumption varies globally due to dietary habits, geographic differences, and environmental conditions. Se’s history, sources, biomarkers, nutritional guidelines, and its deficiency and toxicity implications are discussed. It also provides an in-depth look at the pivotal role of selenoproteins, including their synthesis, various types, functions, and the concerns arising from their deficiency or genetic variations. From supporting the brain, fertility, development, and immunity to regulating thyroid function, these proteins illustrate the multifaceted importance of Se in human biology. Notably, Se has also emerged as an environmental contaminant that warrants attention. To address this challenge, the contamination sources, remediation strategies, and analysis methods were summarized.