Age is recognized as an important factor in the appearance of autoimmune disease. In a paper that appeared in The Lancet in 1992, investigators assessed the difference in physiological chemistry between healthy centenarians and unhealthy 60- and 70-year olds. The most striking difference was that the healthy centenarians had very low levels of autoantibodies to their thyroid, adrenal, pituitary, hypothalamus (Mariotti 1992). This has led some people to speculate that autoimmunity is the result of environmental exposure to foreign substances. Thus, the immune system may also be suppressed or weakened as a result of lifestyle factors (ie, intake of alcohol, caffeine, tobacco, drugs, sugar, poor diet, and lack of sleep) not associated with a degenerative disease. These lifestyle factors can have a substantial effect on the trends of autoimmune diseases.
As we age, our autoimmune system declines in its effectiveness due in large part to oxidative damage caused by the recurrent presence of significant amounts of free radicals. In addition, proteins can become glycated, that is, a sugar molecule is attached to the protein. The accumulation of these glycated proteins in the body affects the immune system because the immune system sees them as altered proteins with different structure and function (Monboisse 2000; Sasaki 2001; Collison 2002). Regarding these substances as foreign, the immune system develops antibodies against them. The possibility of becoming allergic to oneself, with the associated autoimmunity and inflammation, increases as one accumulates these damaged glycated proteins.
The body is made up largely of proteins, so its health depends upon its freedom from damage (as through oxidation or glycation) as well as its timely removal as part of normal protein turnover. The body's antioxidant system and other lines of defense cannot completely protect proteins. Nature's second line of defense is the body's system for repairing or removing damaged proteins. While some protein repair mechanisms exist, it is difficult for the body to repair most protein damage. Yet, it is essential to efficiently remove aberrant and unneeded proteins to fully protect against autoimmune diseases.
Methods to protect against excessive protein glycation will be discussed later in this protocol.