Some Molecular Science
The human body is made up of many different types of cells and these in turn are composed of many different types of molecules. Furthermore, on an even smaller scale, these molecules consist of one or more atoms of one or more elements joined by chemical bonds. There are about 90 naturally occuring atoms and these consist of a nucleaus which is made up of a combination of different numbers of neutron and proton particles and which is circled by 1 or more electrons which form outer shells, depending on their number. Protons have a positive charge (neutrons have no charge) and their number determines the number of electrons (which are negatively charged) that surrounding the atom nucleus usually co-existing in pairs. Electrons are involved in chemical reactions and are basically what bonds atoms together to form molecules.
The number of electrons that form part of a molecule is very significant since its what determines to a large extent the chemical behavior of the molecule. In a basic sense, matter that has particles with outer shells full of paired electrons will not react chemically (its considered ‘inert’). Because the nature of atoms is to seek to reach a state of maximum stability, particles and atoms that have an un-paired electron in their outer shell will attempt to gain other electrons to pair them up with, either gaining them from other particles or by bonding with other particles to share electrons – this is basically what we refer to as a chemical reaction.
Electrons have a positive charge and when they are moved between molecules so the charge of those particles changed as well – the process of a particle losing some charge we refer to as oxidation. The change in the theoretical total charge that a particle holds is referred to as the change in its oxidation state.
Free Radicals
The term ‘free radical’ comes from chemistry and is used to describe at particle, atom or ion that has one or more unpaired electrons. They are very unstable because of the laws that force them to seek electrons from other particles or atoms. If a free radical particle can ’steal’ an electron from another particle then that particle is left with an un-paired electron and so it becomes a free radical and so on, causing a chain reaction in some cases. These chemical reactions play a very important role in combustion, atmospheric chemistry many other chemical processes, including human physiology.
Free radicals play a number of important roles in our biology, some of which are necessary for life, such as the intracellular destroying of bacteria and viruses. However, stress on the human body, both physical and emotional, and environmental factors such as pollution, radiation, cigarette smoke and herbicides can also spawn free radicals. Since free radicals are necessary for life, the body has a number of mechanisms to minimize free radical induced damage and to repair damage which does occur, however because of their reactivity, free radicals can cause unwanted side reactions which result in cell damage as the physiological processes of reacting particles that make up the bodies cells changes the cell structure. Free radical damage is also cumulative so the effects increase with age.
When the process of oxidation in the human body, or in any other organic matter, causes tissue damage then this is often referred to as oxidative stress.
Antioxidants
An antioxidant is a molecule that is capable of preventing this transfer of electrons – the process of oxidation. Antioxidants can terminate the chain reactions that occur when lots of particles interchange electrons because of their instability, by removing free radical intermediates, and inhibit other oxidation reactions by being oxidized themselves ie. antioxidants are molecules that can remain stable in effect, even after losing an electron . Since the process of oxidation is important in some biological processes the body naturally maintains a system of multiple types of antioxidants, such as various enzymes and vitamins C and E.
Vitamin E is an abundant fat-soluble antioxidant in the body and is very effective at neutralizing the oxidation process. It is probably the most important combatant against the harmful effect of lipid peroxidation – the creation of unstable molecules containing more oxygen than is normal.
Vitamin C is an abundant water-soluble antioxidant and acts primarily on cellular fluid. This antioxidant is understood to be very important in halting free radical formation caused by pollution and cigarette smoke.
Skin Care
Maintaining healthy levels of antioxidants is one thing we can do to help prevent the harmful effects of oxidative stress on skin tissues. Skin care products that claim to combat fre radical damage do so by including antioxidants such as vitamins E and C in their formula. Do they work? There is lots of conjecture and lots of arguments and scientific research for and against. Until we understand more, one of the most sensible approaches to helping maintain healthy skin is ensuring you try and eat a well-balanced diet with fresh fruit and vegetables, especially those rich in vitamins C and E – this will help ensure you keep your antioxidant levels up.
Once the process is started, it can cascade, finally resulting in the disruption of a living cell.
Normally, the body can handle free radicals, but if antioxidants are unavailable, or if the free-radical production becomes excessive, damage can occur. Of particular importance is that free radical damage accumulates with age.