Human beings were designed to live to 120, according to Walter M. Bortz II, MD, in his book “We Live Too Short and Die Too Long.”
People could live to 120 if abnormalities such as disease, trauma, behavioral mal-adaption and self-destruction were controlled. Bortz says too many people avoid preventive health care.
Much that passes as aging is not due to age at all but to disuse. Put a broken leg in a cast and in a few short weeks, it will wither and appear as a leg many decades older. Similarly, all of our body functions-digestive, cardiovascular, respiratory, sexual and mental-are highly keyed to use.
“Use it or lose it” does relate to length and quality of life. Dr. Robert Butler, first director of the National Institute on Aging, has said, “We haven’t found any biologic reason not to live to 110.” Bortz estimates that our biogenetic maximum life span is 120 years, but most of us die in late middle age, around 76.
Aging is a complex process involving many body systems. Changes occur in the body’s cells that alter the cells’ ability to function or respond to external stress or infection. Aging may be caused by damage that occurs in various body systems throughout life, including wear-and-tear, harmful substances that we breathe and eat or natural processes with the body.
The theory is that if the causes of the “damage” can be removed or corrected, life expectancy could be extended.
All organs and vital functions show a gradual reduction in capacity with the passage of time. However, no one has been proven to die of “old age.” Most deaths are the result of a sharply localized problem such as hemorrhage, a blood clot blocking a critical artery or a strategically placed tumor.
Experiments have shown that when one takes the number of total cell divisions and multiplies it by the cell life of each cell, one calculates roughly 120 years as the theoretical maximum human cell life, Bortz says.
The increase in life expectancy from 45 to 76 years in the last 75 years appears to have come about as a result of improvement in medical care before and around the time of birth; the conquest of most infectious diseases; a general improvement in nutrition and better public hygiene (with the exception of environmental pollution).
Such a dramatic lengthening of the average life span has never occurred before.
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