To understand the way that free radicals and antioxidants interact, you must first understand a bit about cells and molecules. This is a quick course in Physiology/Chemistry lesson: The human body is composed of many different types of cells.
Molecules are atoms of one or more elements that are joined by a chemical bond. Cells are made up of many different molecules.
Atoms are made up of a nucleus, protons, electrons, and neutrons. The number positively charged particles (protons) in the nucleus of the atom is what determines how many negatively charged particles (electron) will surround the atom.
Electrons are responsible for the chemical reactions that take place inside the atom as well as the substance that holds the atom together to form molecules. Electrons orbit the atom in one or more shells.
The innermost shell is full when it has two electrons. When the first shell is full, electrons begin to fill the second shell. When the second shell has eight electrons, it is full.
The most important structural characteristic of an atom for determining its chemical behavior is the number of electrons in its outer shell.
An atom that has a full outer shell does not enter in chemical reactions. Atoms seek to reach a state of maximum stability by one of the following:
Eradicate or pick up electrons to fill or empty the shell
Bonding with other atoms to share electrons to complete the outer shell
Atoms regularly complete their outer shells by sharing electrons with other atoms. Sharing electrons allows the atoms that are bound together to satisfy the conditions of maximum stability for the molecule.
Usually when a split occurs, it never leaves the molecule with an odd, unpaired set of electrons. However, when bond does split, free radicals are created–they tend to move and react quickly to other compounds as they begin to attempt to capture as many electrons as they can to achieve maximum stability.
Traditionally, free radicals attack the nearest stable molecule they come across– “stealing” its electron. When the “attacked” molecule loses its electron, it too now becomes a free radical thus starting a chain reaction. Once this process is started, it can cascade and finally result in the disruption of a living cell.
During metabolism, free radicals will normally arise–there are even times when the body will naturally create free radicals for situations like neutralizing viruses and bacteria. Another way free radicals enter the body is by pollution such as radiation, smoke, and insecticides.
The body usually can defend free radicals, however when antioxidants are unavailable or the production of free radicals becomes too much, damage can occur. The most important thing to remember here is that free radical damage hastens the aging process.
