Antioxidants effects in health: The bright and the dark sides

As a double-edge knife, oxidative stress (OS) has shown paradoxical behaviors toward beneficial/harmful responses on human health. In this regard, while the high levels and long-lasting exposure to OS is associated with disease development, low/moderate levels of OS could be a natural defense system in the human body. From the mechanistic point, resilience pathways and related signaling mediators (e.g., Nrf2, catalase, glutathione, heme oxygenase, etc.) are responsible for the final outcome of OS which could be modulated by enzymatic and nonenzymatic approaches. Additionally, natural compounds are promising compounds in modulating OS. Altogether, providing a balance between OS and antioxidants could be a critical step forward in a healthy system. © 2022 Elsevier Inc. All rights reserved.