This review article explores the dual nature of oxidative stress, highlighting both its harmful and beneficial aspects for human health. Oxidative stress is defined as an imbalance between the production and accumulation of reactive oxygen species (ROS) and the body's ability to detoxify them. ROS, such as superoxide radicals, hydrogen peroxide, and hydroxyl radicals, play crucial roles in cell signaling and metabolism but can cause significant damage when overproduced due to environmental stressors or xenobiotics. The article discusses the physiological roles of ROS, including their involvement in immune responses, cell signaling, and mitogenic responses, while also detailing the detrimental effects of oxidative stress on various diseases, such as cancer, cardiovascular disease, neurological disorders, respiratory diseases, rheumatoid arthritis, and kidney diseases. The review also examines the role of antioxidants, both endogenous and exogenous, in mitigating oxidative stress. Vitamin E, flavonoids, and polyphenols are highlighted for their potential health benefits, particularly in preventing and treating diseases. However, the article notes that these antioxidants can have adverse effects under certain conditions. Additionally, the article explores the therapeutic potential of prooxidant agents, such as ascorbic acid (vitamin C), polyphenols, and ionizing radiation, in cancer treatment, despite their well-known harmful effects. In conclusion, while oxidative stress is generally considered harmful, it can also be harnessed as a therapeutic tool when managed carefully. The article emphasizes the need for further research to understand the complex interplay between oxidative stress and human health, and to develop strategies to optimize its benefits while minimizing its adverse effects.This review article explores the dual nature of oxidative stress, highlighting both its harmful and beneficial aspects for human health. Oxidative stress is defined as an imbalance between the production and accumulation of reactive oxygen species (ROS) and the body's ability to detoxify them. ROS, such as superoxide radicals, hydrogen peroxide, and hydroxyl radicals, play crucial roles in cell signaling and metabolism but can cause significant damage when overproduced due to environmental stressors or xenobiotics. The article discusses the physiological roles of ROS, including their involvement in immune responses, cell signaling, and mitogenic responses, while also detailing the detrimental effects of oxidative stress on various diseases, such as cancer, cardiovascular disease, neurological disorders, respiratory diseases, rheumatoid arthritis, and kidney diseases. The review also examines the role of antioxidants, both endogenous and exogenous, in mitigating oxidative stress. Vitamin E, flavonoids, and polyphenols are highlighted for their potential health benefits, particularly in preventing and treating diseases. However, the article notes that these antioxidants can have adverse effects under certain conditions. Additionally, the article explores the therapeutic potential of prooxidant agents, such as ascorbic acid (vitamin C), polyphenols, and ionizing radiation, in cancer treatment, despite their well-known harmful effects. In conclusion, while oxidative stress is generally considered harmful, it can also be harnessed as a therapeutic tool when managed carefully. The article emphasizes the need for further research to understand the complex interplay between oxidative stress and human health, and to develop strategies to optimize its benefits while minimizing its adverse effects.