In the cultures of Far East Asia, getting older used to increase one's social status. In modern times, the Confucian principle of reverence toward the older generations still lingers.
In modern Western society, the general view of aging is closer to that of ancient Greece, where beauty was worshipped and youth was adored.
Recently, researchers have started to make breakthroughs in this field.
Caloric Intake and Oxidative Stress
Scientists have proposed a theory that low caloric intake could slow down aging after observing that caloric-restricted rats live almost 60 percent longer than expected.
Closely related to the caloric theory is the theory of oxidative stress. Cells use food and oxygen to generate the energy that keeps the body running. It is estimated that three percent of oxygen consumption goes to producing free radicals, molecules that are highly reactive and will attack the structures inside the cells. It is estimated that the DNA in each cell will be attacked 100,000 times in a 24-hour period.
Fortunately, there are repair systems, but they are not foolproof. Many people believe that oxidative stress, which leads to a gradual destruction of intracellular structures by free radicals, is one of the major causes of aging.
Number of Cell Divisions Limited
Molecular biologists have long known that human cells can divide a limited number of times. This phenomenon, known as replicative cell senescence, has been extensively studied in fibroblasts, a type of cells commonly found in connective tissue. Viable fibroblast taken from humans and cultured in vitro start dividing vigorously, but as time passes, the proliferation rate gradually decreases. After approximately 60 rounds of cell division, they stop dividing and cannot be made to divide any further.
Whereas a fibroblast may only go through 60 cell divisions, human stem cells (not fully differentiated cells) seem to be able to divide millions of times. Stem cells are found in almost all tissues.
However, every time a stem cell divides, some mistakes are made in the DNA-copying process and these errors accumulate over time. Sooner or later, it will have accumulated so many errors in its DNA that it transforms into a tumor cell.
The Way Out
Many people pin their hopes on physical training. Whereas exercises indeed can strengthen the body and lessen morbidity, they cannot slow down aging per se.
Theoretically, physical exercises make the body age more quickly, since they will make you eat more (increase caloric intake), boost the cellular metabolism (more oxidative stress) and speed up the turnover of cells.
Much contemporary research suggests that mind-body practices can slow down aging. It was known among the ancient Chinese that those who practiced Tai Chi were healthier and lived to be much older than others. Research on yoga has found that the practice significantly decreases oxidative stress. Recently, a study on qigong practitioners found that the turnover of cells had been greatly reduced by the practice.
Mind-body methods are probably the best and most affordable way to stay younger longer.
Resources:
Li QZ, Li P, Garcia GE, Johnson RJ, Feng L. Genomic profiling of neutrophil transcripts in Asian Qigong practitioners: a pilot study in gene regulation by mind-body interaction. J Altern Complement Med. 2005 Feb;11(1):29–39.
Yadav RK, Ray RB, Vempati R, Bijlani RL. Effect of a comprehensive yoga-based lifestyle modification program on lipid peroxidation. Indian J Physiol Pharmacol. 2005 Jul–Sep;49(3):358–62.