Abstract

Immune homeostasis relies on a dynamic equilibrium between oxidative stress, redox signaling, and the 
antioxidant systems that buffer reactive oxygen and nitrogen species generated during normal metabolism and 
inflammatory responses. Both endogenous antioxidants-such as glutathione, thioredoxin, uric acid, and enzymatic 
systems-and dietary antioxidants derived from fruits, vegetables, spices, and phytochemicals collectively maintain 
this balance. Disruption of redox homeostasis leads to immune dysfunction characterized by exaggerated 
inflammation, impaired pathogen clearance, altered lymphocyte differentiation, and progression of chronic 
metabolic and inflammatory diseases. This review synthesizes current mechanistic insights and emerging 
translational evidence on how dietary and endogenous antioxidants regulate innate and adaptive immunity 
through redox-sensitive pathways, including Nrf2, NF-κB, HIF-1α, and mitochondrial signaling. It further 
highlights clinical implications, therapeutic opportunities, and remaining research gaps required to bridge 
experimental knowledge with real-world clinical application. Understanding the interplay between antioxidant 
systems and immune regulation offers an evidence-based foundation for developing targeted dietary, 
pharmacological, and lifestyle interventions to restore immune balance in diverse pathological contexts.