Many years ago, nobody bothered much about the maximum lifespan of man. It refers to the highest number for which a person can live, provided the environment is ideal. But then, with time, it became a subject of interest. Modern inquiries into this subject matter started around the early 20th century. One researcher said at that time, our cells can continue to divide infinitely in ideal environmental conditions. That led to the belief that we have the potential to be immortal if the environment is ideal. About 50 years later, Leonard Hayflick faulted the earlier theories of aging. He was able to prove that our cells have a limit beyond which they can no longer divide. He said man’s maximum lifespan is about 115 years. Over the years, experts have made more discoveries, and they keep developing new theories of aging and improving upon the old ones.
The issue of lifespan is so closely related to aging. Without aging, there will be no limit to lifespan. Well, many concepts and theories exist about aging. Experts have tried in different ways to explain the mechanisms by which age-related changes occur. Of all these theories, none has sufficiently explained the aging process. But they all bring a measure of understanding to the process. However, some of these theories contradict a few others. So then, there are both valid and invalid theories.
Different Concepts of Aging
There are various ideas behind the aging phenomenon, referred to as aging concepts. You should first understand the aging concept before seeking to know how it happens. So here are the different concepts:
- Chronological Aging: This concept refers to the passage of time. That is, how long you have been living. That is what you answer when you are asked, how old are you?
- Biological Aging: Some people refer to this as senescence aging. It is the progressive decline in a person’s functional characteristics. That will include both physical changes and internal changes that slow a person down in their older years.
- Psychological Aging: That refers to the progressive changes in personality and mental functioning that happens with age. It usually shows in a person’s carriage and actions. Some people are chronologically young but act like older people. Some others are old, but they act and look like younger people.
- Social Aging: This refers to how your relationships and roles change with age. This is usually a function of what your society considers to be socially acceptable for you at your age. Some societies have a positive view of aging, while some have a negative view. This goes a long way in determining how enjoyable the experience of social aging will be.
- Cognitive Aging: This concept deals with how cognitive processing declines with age. This also includes impairments in memory, learning abilities, intellectual competence, and reasoning as you grow older.
The Theories of Aging
The different aging theories supply different perspectives from which we can understand aging. They give unique insights into the aging process. There are biological, psychosocial, and developmental aging theories. While they are all clinically important, the most-used is biologic theories.
These theories seek to explain the reason for some physical changes that occur due to aging. Experts try to find out the most significant biological factor in aging and longevity. Some of these theories are as follows:
1. Biological-clock theory
This theory says there is a Biologic clock in each of us. According to the proponents, the clock begins to tick from when a baby is conceived. This “ticking” refers to cell division.
This theory says that our genes determine how many cell divisions can occur in your body. With time, certain changes begin to occur as more cell division occurs. When the last “tick” occurs, in certain organs, they begin to fail. One classic example they give for this theory is menopause.
2. Molecular Theories
There are quite a few theories under this category. These theories propose aging as a process modulated by some genetic materials. Experts say that there are hidden genetic codes in our molecules that predetermine growth as well as decline. Some common examples are the error theory and the somatic-mutation theory.
3. Cellular Theories
Cellular theories see aging as a consequence of cellular damage. With time, more and more cells damage until it begins to affect your body’s overall functioning. Some common examples are the free-radical theory, clinker theory, crosslink theory, and the wear-and-tear theory.
The free-radical theory says that free radicals can form reactions with and destroy healthy molecules. This is because they carry a negative charge, thus creating unbalanced energy. This negative energy turns balanced molecules into unbalanced molecules. As damage progresses, functional declines begin to occur.
Psychosocial and Developmental Theories
We mentioned that aside from biological aging theories, there are also psychosocial and developmental theories.
Psychosocial aging theories in this category see aging as a combination of behavioral changes, as well as changes in relationships and roles with age. This has more to do with how people adjust to aging, as well as how aging itself occurs.
Examples of these theories include disengagement theory, continuity theory, subculture theory, and activity theory. Activity theory, for instance, proposes that you must remain active to age successfully. This theory says that you must actively participate in mental and physical activities to function well in your old age.
Developmental theories try to join the dotted lines in personal and personality adjustments throughout life. Theories in this category identify life-oriented tasks in aging individuals. Examples include Erikson’s, Newman’s, Havighurst’s, Jung’s, and Peck’s theories.
The concept of these theories is to identify the characteristics and traits that people develop while they are young. It then traces these traits and how they change through life and as aging occurs.
Depending on how a person accepts these changes without regrets, they may either gain wisdom or experience despair in old age. In most cases, however, it’s a mix of both.
These theories of aging all portray an accurate view of aging from different perspectives. But none of them offers a full explanation. To understand aging better, we must compare the different views.