Aging Changes in Organs - Tissue - Cells

See all Pictures & Images

Aging theory

No one really knows how and why people change as they get older. Some theories claim that aging is caused by accumulated injuries from ultraviolet light, "wear and tear" on the body, by-products of metabolism, and so on. Other theories view aging as a predetermined, genetically controlled process.

However, no theory sufficiently explains all the changes of the aging process. Aging is a complex and varied process that varies in how it affects different people and even different organs. Most gerontologists (people who study aging) feel that aging is the cumulative effect of the interaction of many lifelong influences. These influences include heredity, environment, cultural influences, diet, exercise and leisure, past illnesses, and many other factors.

Unlike the changes of adolescence, which are predictable to within a few years, each person ages at a unique rate. Some systems begin aging as early as age 30. Other aging processes are not common until much later.

Although some changes that typically occur with aging, they occur at different rates and to different extents. There is no reliable way to predict specifically how you will age.