Antioxidants, whether naturally occurring or synthetic, play a critical role in protecting cells from oxidative damage caused by reactive oxygen species (ROS). They contribute to human health by scavenging free radicals, chelating metals, and modulating cellular signaling pathways. These compounds are abundant in fruits, vegetables, cereals, legumes, and medicinal plants, and their consumption has been linked to the prevention of chronic diseases, including cardiovascular disorders, diabetes, neurodegenerative conditions, and certain cancers. This review provides a comprehensive overview of antioxidant classification, mechanisms of action, dietary sources, and health benefits, covering both endogenous and exogenous compounds. Selected examples from the author’s research on medicinal plants and winter vegetables in Bangladesh illustrate variability in antioxidant activity and highlight the nutritional significance of carotenoids and flavonoids, providing context for region-specific dietary antioxidant intake. Integrating these findings with strategies such as biofortification, sustainable agriculture, and functional food development can enhance the antioxidant content of crops and support measurable improvements in human health.
Mohammad Zahir Ullah (Sun,) studied this question.