There are several theories for genesis of aging mechanisms, among them the error catastrophy theory is most acceptable for the progressive accumulation of changes in DNA with time associated with the ever-increasing likelihood of disease and death that accompanies advancing age. Free radical theory of aging may well chemically explain the changes including DNA, endocrine, immune response, and collagen bridges. Free radical reactions, ubiquitous in living systems, are of both enzymatic and non-enzymatic origin, both being related each other. The latter involves the copper and iron catalyzed reactions of oxygen with organic compounds, which from reactive intermediates serving to bind the multiplicity of further free radical reactions proceeding continuously throughout cells and tissues into a network of reactions with variable degrees of interaction between them. Biological scavenge systems and substances for protecting the progressive radical chain reactions exist in living systems. The relation of progress in the chain to protective mechanisms may decide aging phenomenon. If the biological scavenge system is progammed throughout life, nutrients for scavenging the chain, including vitamin E, may be available for maintaining healthy aging.