why do we age???

GeneticsAging changes on the cellular basis which is partially determined by genes. Our cells host DNA which sets a fixed number of cell replications. Human bodies are built up of different types of cells: mitotic (dividing), postmitotic, and resting. The capacity of replication of mitotic cells is limited. After a cell reproduced itself a certain number of times, it dies. Every division bears a threat of alteration; the older the cell, the more alterations it has undergone. Then the moment comes when the cell blueprint is so changed, that the cell cannot replicate itself properly anymore. Other types of cells either have very limited ability to divide, or cannot reproduce themselves at all. When nerve, kidney, or heart muscle cells are lost they are not replaced. However, not only genes affect the aging process. Approximately 40 percent of a cell aging depends on the life style of an individual.
Metabolic Rate
Each living species has a fixed maximum life span. Some scientists believe for humans it is 1380 months (115 years), for a Chimpanzee - 534 months, for a dog - 408 months, and for a mouse - 42. Other scientific calculations tell that an approximate maximum life span of humans is 125 years. Free radicals, a product of metabolism, destroy cells and cause aging on a cellular level. The metabolic rate explains how we accelerate aging by spending our energies in vain. Metabolic rate is defined as calories burned per gram of body mass per day. We burn our energies when we grow, repair from illnesses, digest food, exercise, work, or become stressed. The problem is that the reserve of energy each of us has got is not unlimited. All living beings use up a fixed amount of energy during their lifetime. When the reserve is depleted, the system shuts down. The faster you consume your energy potential, the sooner you wear out and age. It occurs when our contaminated bodies spend more time on digestion of "dead" food, when we consume more food than needed, when we exercise too much or get exposed to air and water pollutants. We also age faster when we infect our minds with negative thoughts and our souls with negative emotions. If you learn how to preserve your energy you can delay aging. One of the attempts to limit consumption of energies is a caloric restriction therapy. There is also plenty of other methods of energy conservation and extension of the life span.

Energy and Caloric Restriction
When caloric intake is kept to about 30-40 percent of what was normally eaten but a nutrient-rich diet was maintained, the metabolic rate slowed down, aging process maybe delayed, the life span may increase, the blood cholesterol and blood sugar may decrease, physical activity, intellectual skills, and may rejuvenate a more youthful appearance. However, caloric restriction is not the only way to balance metabolism of the body. Adopting a strict lifestyle of sobriety from eating and wine drinking, yoga exercisesmay also help balance the energies and metabolism. You consume fewer calories naturally when your internal organs function properly and when your body are able to absorb more nutrients from what you eat. Fasting is another way to detoxify your body and restore your bodily functions.