The process of aging of a human body as a whole has not been fully explored, and therefore there is no single point of view on the causes of age-related changes. However, studies on the mechanisms of aging have an unconditional practical value enabling to discover the most effective methods of slowing it down.
There are several different approaches to classification of theories describing the mechanisms of aging. We decided to identify three key groups of theories based on their definition of the main aspect of aging: metabolic, regulatory or genetic aspects. Each of these approaches existing today can be attributed to one of these groups one way or another.
Metabolic aspect is a key element in theories of fatigue damage accumulation. This group of theories emphasizes gradual impact of the inevitable internal changes and the external environment on all body systems. Such impact disrupts biochemical processes in the body. It has three main theories: free-radical theory, nutrition theory and cross-linkage theory.
This theory was first propounded in the 50s of the 20th century by the American gerontologist Denham Harman. According to Harman’s concept, the so-called free radicals have a decisive influence on the processes of biosynthesis. Free radicals are being formed in the cells as a result of biochemical processes and they cause damage to proteins, lipids and other biological molecules, which in turn triggers the aging mechanism.
Since the appearance of this theory, it has already been proven that free radicals can cause more than 80 noncommunicable diseases, including cancer, arthritis and a number of heart diseases.
This theory of aging actively supports the use of antioxidants of natural and synthetic origin since these substances help neutralize and prevent the harmful effects of oxidation. The most well-known antioxidants in anti-aging medicine are vitamins C, E and beta-carotene (promotes the production of vitamin A).
Thus, associating the mechanism of aging with the negative effects of free radicals, we can make a conclusion that effective diagnosis and subsequent slowing down of aging processes make it necessary to determine the degree of activity of the antioxidant system enzymes. This can be done with the help of genetic testing which reveals the individual characteristics of the mechanism of cell protection against oxidative stress.
This theory associates the aging process with a lack of vitamins and minerals in the food. We should mention that our ability to assimilate nutrients decreases with age, so the individual diet should also be subject to regular review and adjustment. Otherwise, the deficiency of vitamins and minerals may lead to irreversible changes in the body.
The study of nutritional deficiencies requires analyzing their concentration in the blood and hair. Genotyping (genetic analysis) also helps to identify the individual characteristics of metabolism and the specific features of the digestibility of vitamins and minerals. Restoring the levels of biologically significant elements, we can as well to restore a number of body functions and stop the aging process.
The author of a cross-linkage theory is a biochemist and gerontologist named Johan Bjorksten. According to his approach, the attachment of protein molecules (cross-linking) occurs because of glucose effect. This process entails the destruction of body tissues and cells.
The prevention of early aging in this case involves the correction of nutrition aimed at reducing the level of sugar, as well as leading an active lifestyle. In addition, cross-linkage may be slowed down by taking certain kinds of drugs.
The preliminary diagnostics uses glycosylation markers which can be studied with the help of genotyping.
Theories included in the second group are based on the following hypothesis: aging is nothing more than a predetermined decline in immune or neuroendocrine regulation.
Programmed decrease in the efficiency of the immune system increases the risk of infectious diseases. In addition, the immune system begins to destroy its own cells – therefore, it is possible to identify this mechanism of aging by identifying the amount of autoantibodies.
The reduction of autoantibodies will thus help to correct or even suspend the aging process. It may become possible with the use of immunomodulators.
Just like other theories of aging based on the regulatory aspect, autoimmune theory refers to the concept of hereditary predisposition. Today, the identification of such programs embedded in the genes becomes possible due to a full-scale study of human DNA (genetic analysis).
Neuroendocrine theory associates the aging process with the concentration of hormones in the body. When we are young, the sufficient level of hormones ensures normal functioning of the body, but its decline with age becomes the main cause of rapid aging.
Anti-aging therapy often refers to the study and correction of various hormonal disorders. Diagnosing the level of hormones in the blood and other biological fluids as well as conducting genetic testing enable to develop an individual hormone-modeling therapy which will stimulate the cells to restore metabolic activity to the level of a young body.
In theories related to this group, aging is also considered as a programmed recession where a hereditary predisposition plays the decisive role.
Irreversible changes in DNA, the function of various genes and disruptions in genetic programs, revealing themselves over the years, lead to cell death and affect the functioning of the whole organism. It turns out that some kind of “biological clock” determines body’s growth and aging.
Today, genetic analysis allows to determine the predisposition of the organism to various diseases in advance and significantly reduce the risk of their occurrence.