Many people may think that health means a mere absence of disease but the real definition of health is the state of complete physical, mental, and social well-being.
Aging is a process of physical, psychological, and social change. Health keeps on changing with the age. The process of aging is biologically termed as senescence and it is confirmed by unresponsiveness to high stress, highly available to disease risk and a constant imbalance.
Some experts even treat aging as a disease. Aging is not unavoidable. Some species of trees, fish show very low signs of aging. But in humans and other animals the process of aging has been attributed to the shortening of telomeres a region of repetitive DNA at the end of chromosomes, which protects the end of the chromosome from destruction. When telomeres become too short, the cells die. The incidence of some diseases increases rapidly with aging. Some of them are Cancer, diabetes, arthritis, cataract, and osteoporosis.
Nearly all cancers are caused by abnormalities in the genetic material of the transformed cells. The immortality of cancerous cells is closely associated with the shortening of the telomeres. Similarly arthritis, involving damage to the joints of the body is a cause for the disability in people older than fifty five years. Every species that had its beginning in the form of birth should have its end in the form of death. Variation in health with the age is just the tool that takes them a step nearer to death.
