Why can’t people live forever? Think about it. If the only reason why people age is a hormone that causes aging, why can’t we develop something that can suppress this hormone to let us live forever? If only hormones caused aging, things would be easier. Unfortunately, aging is caused by a plethora of factors that caused quite a stir among doctors and scientists. Aging is such a complex process that scientists don’t have one, but two groups of theories that dictate why and how people age.

Gerontology, or the study of aging, is a relatively new science that today has made huge progress over the last three decades. Long ago, where technology is not enough to support some of sciences endeavors, scientists only looked for one single theory to explain why people age. Today, there are two groups of theories. The first one proposes that aging is a natural process that is programmed into the body’s systems, while the second one proposes that aging is the consequence of cellular damage that worsens over time. Both of these theories involve the complex interaction of behavior, physiology, chemistry, and genetics to dictate how and why aging happens, what we can do to slow it down, and for some scientists, how to stop it.

The Various Theories of Aging

By describing and understanding how people age, scientists and researchers have successfully developed various theories of aging. The two aging theories include programmed theories and error theories. Heres an in-depth description about each one.

Programmed Theories

Programmed theories about aging propose that that human body is programmed to age and that it follows a particular biological timeline. Examples of programmed theories include programmed longevity: a theory that states that aging is the result of genes switching on and off over the length of ones life, endocrine theory: a theory that states that aging is caused by mere changes in the body’s hormones that triggers the body to begin aging, and immunological theory: the theory that states that the immune system is specifically designed to decline in efficiency over time, heightening the persons chance of becoming more susceptible to diseases.

Error Theories

Another division of aging theories include aging theories. According to error theories, aging is caused by the body’s exposure to environmental damage, destroying cells and weakening the body’s organs. According to this branch of theory, people age because of external factors, as opposed to program that state that we are programmed to age. There are a plethora of error theories that scientists continue to study even until today. Error theories include wear and tear: a phenomenon where the tissues and cells of the body wear out, rates of living: a theory that states that the faster organisms use oxygen, the shorter its life becomes, cross linking: a phenomenon that involves the cross-linked proteins accumulating in the body and slowing down the body’s natural processes, free radicals: substances that the body accumulates from the environment that damage the cells and impairs their function, and somatic DNA damage: or the mutation of genes that lead to cell malfunction.

The Role of Genetics in Aging

Countless research and experiments have proven that genetics does play a large role in the development of aging. In one experiment conducted by researchers on the genes of yeast cells, mice, and other organisms, lifespan has been successfully doubled. The significance of these successful experiments on people, however, is still not known, but scientists believe that genes account for about 35% of the variation in the development of aging between people. There are a few concepts about aging and genetics that you may want to know.

Longevity genes are the genes responsible for helping the body live longer. Cell senescence is the particular process in which the cells of the body deteriorate through time. Telomeres are specific structures located in a persons DNA that go through a process of depletion, preventing cells from replicating. Stem cells, one of the most recent discoveries nowadays, are a type of cell in the body that can turn into any type of cell. Stem cells hold the most promise in repairing the damage caused by aging.

Biochemistry and Aging

It doesn’t matter what genes you have, your body is continually going through a process of biochemical reactions that cause damage to cells and in effect, aging the body. Free radicals, for example, are unstable oxygen molecules that damage the cells of the body. In older people, the systems that are responsible for repairing DNA become less effective, once again contributing to the aging of the body. Hormonal changes are also a well known cause of aging, giving birth to the hundreds of HGH or Human Growth Hormone supplements you see today.

Aging is inevitable but it can be slowed. Eating foods that are rich in antioxidants, exercising, eating a balanced diet and practicing mental fitness can help fight the causes of aging and in effect, lengthen your life!