Every single one of our trillions of cells suffers about 10,000 free radical hits daily!
– Bruce Ames, Ph.D. at University of California, Berkeley estimates that (Ames, 1993)
You may have heard about the health benefits of antioxidants, but do you know what an antioxidant is — and how they actually work?
The simple answer is that antioxidants are substances that protect our cells from oxidation (by free radicals).
Antioxidants are dietary substances including some nutrients such as beta carotene, vitamins C and E and selenium, that can prevent damage to your body cells or repair damage that has been done. Another, glutathione (the “master antioxidant”), is manufactured by our own bodies.
Antioxidants work by significantly slowing or preventing the oxidative — or damage from oxygen — process caused by free radicals that can lead to cell dysfunction and the onset of problems like heart disease and diabetes. Antioxidants also improve immune function and perhaps lower your risk for infection and cancer.
Although oxidation reactions are crucial for life, they can also be damaging; hence, plants and animals maintain complex systems of multiple types of antioxidants, such as glutathione, vitamin C, and vitamin E as well as enzymes such as catalase, superoxide dismutase and various peroxidases. Low levels of antioxidants, or inhibition of the antioxidant enzymes, causes oxidative stress and may damage or kill cells.
In your body, the antioxidant process is similar to stopping an apple from browning. Once you cut an apple, it begins to brown, but if you dip it in orange juice, which contains vitamin C, it stays white.
A little Chemistry
Let’s look at what free radicals are. Molecules are composed of atoms bonded together, via the sharing of electrons. Generally, atoms exist in pairs, with each electron of the pair having an opposite spin to the other. When a molecule is split, two things can happen. First, the electrons can stay together. When this happens, we say the molecule has ionized. For example, table salt, which is Sodium Chloride (NaCl), ionizes into two charged ions, specifically a sodium ion and a chloride ion. In this case, the Chloride received the electron pair, and the Sodium lost it. The other thing that can happen is that the electron pair is split. This leaves a highly reactive atom (a free radical), seeking to steal an electron, which sets up a domino effect of electron stealing.
Antioxidants work by offering easy electron targets for free radicals.
Each time you are confronted by the threats in the outer circle of the diagram free radicals are released. The natural reserve of glutathione in the body breaks down under the assault. The effects of oxidative stress are so critical in fact that a new field of medical science has emerged, called ‘Free Radical Biology’ which studies the long list of diseases caused by it. Today it is known that antioxidants help diminish cell damage, slows the harmful effects of aging and lessens the threat of disease. Oxidative stress can be minimized by raising intracellular GSH levels.
If the free radical is not neutralized by an antioxidant it can wreak all sorts of havoc in our bodies. Current research, for example, is pointing to the fact that it is not only the presence of fat in our bodies that leads to plaque formation on our arteries, but the oxidation of fat by free radicals. With cancer, the problem starts when free radicals chip away at the DNA of our cells, eventually causing mutations that lead to malignancies.
The antioxidants provided by vitamins work because they can donate electrons to free radicals, thus neutralizing them. However, this makes the vitamin molecule unstable, and now it needs an electron. This is sort of like passing a very hot potato from person to person until someone finds a place to lay it down. In our bodies, that place is glutathione.
The chemical equation gets fairly technical, but in the end glutathione donates an electron and becomes a stable molecule known as GSH. Glutathione can then be regenerated via an enzymatic pathway that involves lipoic acid. The details of the chemistry involved is beyond the scope of this page, but is well established in the scientific literature. Also well established is the fact that the glutathione antioxidant system is the most important system in our bodies when it comes to the destruction of reactive oxygen compounds (very potent free radicals). (Meister, 1994) Glutathione is often referred to as GSH.
GSH’s metabolic functions include:
- Enhancement of Immune Function
- Elimination of Toxins
- Antioxidant Cell ProtectionElimination of Carcinogens
- Protection against Ionizing Radiation
- DNA Synthesis and Repair
- Protein Synthesis
- Prostaglandin Synthesis
- Leukotriene Synthesis
- Amino Acid Transport
- Amino Acid Transport
- Enzyme Activity and Regulation
Now you know… antioxidants are important to a healthy lifestyle!