The Selenoprotein Axis: A Unified Cross-Organ Framework for Selenium-Dependent Mitochondrial Protection

This narrative review synthesizes a seven-paper hypothesis series into a unified cross-organ framework. The central thesis is that selenium adequacy functions as the rate-limiting upstream variable governing mitochondrial protection across all high-metabolic, oxidatively stressed, end-artery-supplied tissues. The framework encompasses chronic kidney disease, polycystic ovary syndrome, the convergent triad of PCOS and iron deficiency anemia, selenium depletion in controlled environment agriculture, cochlear vulnerability and tinnitus, LAM disease progression, and pulmonary disease. The paper proposes that selenocysteine dependency is the single most consequential nutritional gap in modern medicine not being systematically addressed, and that the food system is structurally worsening it. All claims represent hypothesis-level proposed relationships requiring prospective clinical investigation.