Why do people grow old?

As we all know, as people age, their bodies will slowly age. The aging of the body manifests itself in many aspects. The biggest change is that many body functions are declining. This is a normal physiological phenomenon, and no one can resist it. However, many people do not understand the aging process of the human body, so let me tell you why the human body ages.

Why do people grow old?

Aging is a natural process, and the theory of natural cross-linking of biomolecules has given a relatively systematic explanation of this. When demonstrating the molecular mechanism of aging in organisms, this theory points out that an organism is an unstable chemical system with a dissipative structure. The various biological molecules in the system have a large number of active groups, which will inevitably interact with each other to produce chemical reactions, causing the biological molecules to slowly cross-link and tend towards chemically active stability.

As time goes by, the degree of cross-linking continues to increase, the active groups of biological molecules continue to be consumed and reduced, and the original molecular structure gradually changes. The accumulation of these changes will gradually cause biological tissues to show signs of aging. On the one hand, these changes in biological molecules or genes will manifest as gene products with different activities or even completely changed functions. On the other hand, they will interfere with the recognition and binding of RNA polymerase, thereby affecting transcriptional activity, manifesting as an orderly and gradual loss of gene transcriptional activity, prompting cells and tissues to undergo progressive and regular phenotypic changes and even aging and death.

From a biological perspective, aging is a spontaneous and inevitable process that occurs in organisms over time. It is a complex natural phenomenon that manifests itself as structural and functional decline, and decreased adaptability and resistance. In physiology, aging is considered as the individual development history starting from the fertilized egg to old age. Pathologically, aging is the result of the accumulation of stress and strain, injury and infection, weakening of the immune response, nutritional deficiencies, metabolic disorders, and neglect and abuse.

Many scientists believe that harmful free radicals accumulate in the human body due to exposure to various rays, taking chemical agents, and excessive iron content in food. This free radical is the culprit that causes human aging. Some scientists believe that cell aging is due to the production of certain substances in cells that cause aging. Eugenia, a cell biologist at Rockefeller University in the United States, isolated a special protein from human connective tissue cells. This protein is only found in aging cells that have stopped dividing, but not in young cells. She believes that this protein is a product of cell aging. Perhaps it is these aging substances that ultimately "kill" the cells. If we can find a way to remove aging substances, humans can greatly delay the aging process.