The body produces free radicals during normal metabolic processes. Free radicals are oxygen-containing molecules with an uneven number of electrons. The uneven number allows them to easily react with other molecules.
Free radicals are produced by a variety of normal biological processes including aerobic metabolism and pathogenic defense mechanisms. They can also be a result of external exposures such as radiation, pollutants, and cigarette smoke. Free radicals are highly reactive and are therefore generally short-lived and often unable to leave the subcellular location where they are generated without first becoming reduced.
Because of their high reactivity, they can abstract electrons from other compounds to attain stability. Thus, the attacked molecule loses its electron and becomes a free radical itself, beginning a chain reaction cascade which finally damages the living cell.
Antioxidants are molecules that can donate an electron to a free radical without making themselves unstable. This causes the free radical to stabilize and become less reactive.
The oxidative stress is developed when there is an excess production of free radicals on one side and a deficiency of enzymatic and non-enzymatic antioxidants on the other side.
Oxidative stress can damage cells, proteins, and DNA, which can contribute to aging. It may also play a role in development of a range of health conditions, including diabetes, cancer, and neurodegenerative diseases such as Alzheimer’s. The protection against oxidative damage and chronic diseases is achieved through a variety of endogenous and exogenous antioxidants.
Concept of oxidative stress
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| Rich antioxidants blueberries |
