Free Radical Damage
Our bodies are made up of approximately 100 trillion cells. Each of our cells is like a tiny battery, producing energy through cellular respiration. As we age, environmental toxins and unhealthy foods containing free radicals – such as fried foods – rob electrons from our bodies (a free radical is a molecule, atom or ion that’s missing electrons in the outer orbit). Free radicals can cause cellular and DNA damage and mutations, and are thought to be responsible for many forms of cancer. Free radicals have also been named as the cause of many symptoms of aging, and one current theory (the Free Radical Theory of Aging) even points to the accumulation of free radicals in the cells as responsible for aging itself.
Whether reducing free radicals can extend lifespan is still under debate and the subject of much ongoing research, but what is certain is that free radicals cause poor cell respiration, fermentation, waste accumulation, acid buildup, and pH derangements in the body. In short, they cause the “batteries” of our cells to emit a weaker charge. Congestion occurs, and our cells become less efficient at pulling in nutrients and expelling metabolic wastes.

[...] Free radicals are small oxygenated molecules that possess an unpaired electron. In molecules, electrons generally go around in pairs and if an electron had no buddy then it desperately tries to find one. So desperately, in fact, that as soon as they are born they will steal one from the nearest donor they can find. In some cases that will be a skin cell, in others a low density lipid (LDL) molecule, and in yet others, DNA and proteins such as muscle tissue will be destroyed. [...]
[...] diet, stress, aging and infections all deplete your glutathione. This leaves you vulnerable to free radicals, oxidative stress from training, and infections that can damage your body. Glutathione is an [...]
[...] any chemical reactions involving oxygen are liable to produce by-products known as free-radicals. These are destructive oxygenated molecules that destroy your cells and their means of producing [...]
[...] enough glutathione, it attempts to decrease adenosine triphosphate production so as to minimize the free radical damage. Therefore, increasing glutathione & SOD provides us with the second method to increase [...]