I found this article: "Are Antioxidants the Key to Preventing Chronic Disease?": "Free radicals are atoms or groups of atoms with an odd (unpaired) number of electrons and can be formed when oxygen interacts with certain molecules through a process known as oxidation.
Let's go back to high school Chemistry class, where we learned the cool term "Redox", which basically describes the process of oxidation and reduction when fruits like apples turn brown or when metal starts to rust.
Photo: Study In "What is Oxidation? Definition, process and examples" Chemistry teacher, Ms. Elizabeth (Nikki) Wyman, explains it as such: "When an atom or compound is oxidized its properties change.
For example, when an iron object undergoes oxidation it is transformed because it has lost electrons. Unoxidized iron is a strong, structurally sound metal, while oxidized iron is a brittle reddish powder.
Most of the time, oxidation occurs in tandem with a process called reduction. Reduction is the process of gaining one or more electrons. In an oxidation-reduction or redox reaction, one atom or compound will steal electrons from another atom or compound.
Illustration: Artinaid A classic example of a redox reaction is rusting. When rusting happens, oxygen steals electrons from iron. Oxygen gets reduced while iron gets oxidized. The result is a compound called iron oxide, or rust. Unoxidized or pure iron is distinctly different from the oxidized form that occurs in rust."