Theory of Aging

Aging is a complex set of processes that involve a diverse set of conditions and reactions. This is why the aging process has been very difficult to define; it is also why there are multiple theories on the process of aging. The processes of aging can be divided into two groups: the amassing of various degrees of damage to the cells and the genetically programmed process of aging.


Microaccidents are random occurrences of various natures that can cause damage to the key structures in the body on a microscopic level. An example of this would be free radicals, which are very sensitive by-products of normal cellular respiration. These free radicals can cause random damage to key molecules such as proteins, DNA and lipids. The cell membranes with are rich in unsaturated fatty acids are particularly susceptible to free radicals because they are very sensitive and reactive to minor intrusions. Mutagens, what are the chemicals that have the ability to react with DNA and change its genetic makeup, can destroy or disrupt the function of the genes. Certain chemicals, such as aldehydes, can tie together or cross link cellular components, lessening their ability to move and function. Although some substances that produce molecular damage originate in the environment (e.g. toxins or ultraviolet rays) can be avoided, many the dangerous elements are a natural functioning part of the metabolism.

Potentially damaging molecular occurrences take place in the body's cells all the time. The bulk of them do not cause long lasting damage because the wound is fixed almost immediately by reparation enzymes. A small number of lesions are passed over by the repair systems and these stay damaged for the long run. Lesions that have not been repaired accumulate; it is then that they begin to have an effect on the vital cellular functions. As we get older, the accumulation of damage that has not been repaired grows, partly because the repair functions themselves have lower levels of efficiency and can even be damaged themselves.

The time span of aging

When age research was in its early years, there was a fervid debate about the existence of aging clocks. Single cell organisms and some of the more primitive species do not have aging mechanisms. However, there is now considerable evidence that more complex beings, such as mammals, have multiple types of aging clocks. The majority of normal cells in more developed organisms have a "clock" in the sense that the cells can withstand only a finite number of divisions - as opposed to bacteria, which can grow indefinitely. There also appears to be a "central clock" which is situated in the brain. This clock controls the speed of both development and aging in the organism. There are other kinds of aging clocks, an example of which is menopause, the time when a woman's reproductive functions shutdown. These secondary clocks are to some extent reliant on the pace of the central and cellular clocks.

There is a big difference between biological clocks and regular clocks. The speed of biological clocks can vary by tremendous amounts between individuals and it is even more diverse between different species. Various environmental events and factors can make the biological clock slow down or speed up. Stress, excessive eating and some insufficient levels of certain nutrients can increase the speed of the aging clock. Lowered stress levels, and certain therapies that renew certain brain structures, specifically the hypothalamus and the pituitary gland, can retard these clocks. In rodents, a low calorie diet begun before sexual maturity has been shown to cause a massively increased lifespan. This is attributed to the slowing of the biological clock. Sadly, this method of strict diet is not a viable alternative in humans as severely lowered levels of caloric intake when young can cause brain damage. However, it is possible that even a moderate limitation of caloric intake in adults can help to slow the aging clock. Statistical studies of the population show that staying close to an ideal body weight is very effective in maintaining longevity in humans.

Free radicals are the chemicals in the body that have an unpaired electron This means that they are very dangerous as they can behave in a erratic manner which can be very damaging to the effective functioning of the body.
DNA is the critical molecule of life: it is the blueprint of the creature encoded in the genes. DNA is an indispensable part of the cell. Other parts of the cells such as the proteins, lipids and RNA can be replaced if need be. DNA, if lost or damaged cannot be replaced.
Could aging be explained as what happens once cells have reached the Hayflick limit and are no longer able to divide? There is no conclusive answer to that question at this time. It seems that in certain tissues, including the skin and the lining of blood vessels the Hayflick limit may be a key to the aging process.
Is there a centralized aging clock in humans that dictates the pace at which all of the bodily systems run? Yes and No... Studies have not yet found a specific central mechanism that is solely responsible for aging. However, there is a system of development.
Certain substances that contribute to the aging process can be avoided. A good example of this is tobacco tar. Other contributory substances are not as easily avoided as they are key parts of the metabolism. The best example of this is glucose.
The majority of energy that is produced in the cells is done by the mitochondria. Cell function is dependent on the mitochondria providing energy to the rest of the system. Mitochondria are also the main factor behind free radical damage.
One of the most important defense mechanisms in the body is inflammation. It is a key to survival but at the same time appears to add to the pace of aging and the speed of the onset of degenerative diseases.
The body's metabolism produces waste on a regular basis. The majority of bodily waste is expelled through breathing, urine, feces and sweat. The most easily disposable waste is that which is composed of small molecules like urea, carbon dioxide and electrolytes.
Stress has been closely linked to the development of age related diseases and to the aging process as well. Stress response is basically a complicated adaptive reaction in the body.
There are two commonly asked questions about the lifespan of humans. The first is why does the rate of aging differ so dramatically among different species of animals? The second one is why are there more short lived species than long lived ones?
Research on the prolonging of life, studies of people over 100, historical records, and common sense all show us that to live a long life you need to do at least some of the steps in this article.
The greater our comprehension of the aging process the more ways that scientists find to try to extend the average life span. Ironically, the most effective means of anti-aging intervention has been the same for the past 50 years; eating less!!