Selenium Speciation Analysis in Foods

Selenium is an essential micronutrient that plays a key role in numerous metabolic pathways and in maintaining human health. As its deficiency affects a substantial proportion of the global population, consuming selenium-rich foods is an important strategy to increase dietary intake and reduce the risk of associated chronic diseases. However, total selenium content alone is insufficient to assess food quality or predict health effects, as individual selenium species, whether inorganic or organic, differ markedly in bioavailability, metabolic pathways, and physiological functions. Consequently, detailed knowledge of selenium speciation is essential for the reliable evaluation of selenium-enriched foods. Despite significant methodological advances, selenium speciation analysis remains challenging. Preserving species integrity during extraction, preventing interconversion, and achieving adequate recovery continue to pose major obstacles. This review summarizes recent advances in analytical approaches for determining selenium species in foods, with particular emphasis on the importance of reliable data on the bioavailability and safety of different selenium forms.