Selenium: A Key Element in Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) is a multifactorial and complex condition of the gastrointestinal tract shaped by host genetics, immune dysregulation, gut microbiota and environmental determinants, with a steadily rising global prevalence. Although the etiology of IBD remains incompletely understood, chronic inflammation accompanied by oxidative stress, immune dysregulation, and gut dysbiosis is widely recognized as a hallmark of the condition. Given the frequent occurrence of undernutrition in IBD patients, the role of vitamins and micronutrients in modulating disease activity has been recently explored. Selenium (Se) is universally recognized as an essential trace element due to its diverse physiological functions, including potent antioxidant activity, anti-inflammatory effects, immunomodulatory properties, and the ability to influence gut microbial composition and diversity. This comprehensive review examines current evidence on the relationship between Se status and IBD, integrating epidemiological and experimental findings, elucidating the underlying biological mechanisms, and introducing Se nanoparticles, a viable therapeutic option using Se in IBD management.