Life Expectancy: Man has always been curious to know for how long he, his loved ones, enemies, and animals he is keeping will live.
The exact time for which organism is going to live is only known to Almighty Allah but the knowledge He has given to man, helps the man to estimate and speculate the life of an organism.
Man has developed a formula for calculating the life expectancy of different animals including him using the available knowledge of mathematics, statistics, and computer sciences.
Scientists describe the life expectancy as the most likely number of years remaining for a living being of a given age to live. In order to calculate life expectancy, first, the crude death rate of organisms in the population at each age group is calculated. This group is then used to calculate the life table.
From the life table, the probability of survival of age group is calculated. From the life table the possibility of persistence of age group is calculated and finally, the life expectancy is worked out using specially designed statistical formula. Now a computer program has also been developed for the calculation of life expectancy.
In the USA, at the moment, it is 77 years; in China and India, it has increased from 40 years to 63 years. In East European countries and Africa, the life expectancy decreased between 1960 to 1980s due to political unrest, wars, and AIDS.
The average human life in Zambia and Japan is 37 and 81 years respectively. 122 years is the oldest age figure recorded in humans, however, in Asia, some people are stated to have lived over 150 years.
The increase in life span in human is due to a number of factors. One factor is the environment in which an organism lives. In a polluted environment, the life expectancy declines whereas in less polluted areas the chances of survival increase many folds.
In addition to environment, diet is another important component for survival: A balanced and sufficient diet plays a pivoting role in healthier living. Better health conditions like advanced diagnostics methods, improved surgical techniques, effective antibiotics, vaccination, health education, and better personal hygiene also play a key role in increased life expectancy.
There remains a significant difference in the life expectancy of men and women in developed countries, with women outliving men due to the use of alcohol. On the other hand, the life expectancy is quite low due to the inadequate supply of food and high mortality rate during childbirth in under-developed countries.
In recent years, the factor that seems responsible for high mortality despite enormous advancement in science and technology is obesity. The major cause is the overuse of fast food. It causes diseases like cancer, heart diseases, and diabetes, etc.
Tobacco smoking and other such addictions cause pollution, AIDS, natural calamities like earthquake, flood, drought, fire etc. By taking proper health measures we can increase our healthy life span but in the end, I just want to say that eternal life is the real life so we should try to improve that one.