Body processes

Life Expectancy – Function, Task & Diseases

Life expectancy

Life expectancy is calculated on a statistical basis and always refers to a population in the same geographical area with the same living conditions. It is determined using mortality tables. In addition, life expectancy is only valid at a specific point in time and can change over time.

What is life expectancy?

Life expectancy indicates the average length of time that a living being will live after a defined period of time. It is determined using a mortality table based on past mortality statistics and future model assumptions.

Life expectancy is usually calculated from the time of birth, so that it covers the entire human lifespan. With increasing age, however, the life expectancy of the surviving population of the corresponding age group increases statistically. This is due to the fact that those who have already died in this age group are no longer included in the statistics from the calculation period.

The calculation of life expectancy is based on the extrapolation of current living conditions into the future. However, the life expectancy to be determined can change at any time due to changes in living conditions.


Life expectancy is influenced by many factors. These factors arise e.g. B. from local, cultural and general living conditions. In order to determine in detail how long the lifespan of a currently living person is statistically, local influences should be recorded in addition to influences from society as a whole.

Local influences are expressed, for example, in the given environmental conditions. Among other things, it is crucial for people whether they are constantly exposed to pollution from traffic or the surrounding industrial plants. Does he live in the city or in the country? How high is the stress level at work? What other occupationally harmful influences are there? The medical care in the corresponding residential area also plays a role. These are factors that are of local origin.

General factors relate to the given economic living conditions of the entire country, general medical progress, the nutritional situation or general health awareness.

In contrast to previous generations, the basic economic living conditions have improved significantly. Economic emergencies that lead to catastrophic famines are now impossible in all Western industrialized countries. Even military conflicts, which used to influence general life expectancy, no longer take place in Western Europe today.

Healthcare has made revolutionary advances in combating serious fatal infectious diseases . Many infectious diseases can now be effectively combated with antibiotics or have been almost eradicated through mass vaccination . The fight against epidemics in particular has greatly increased life expectancy in recent decades.

Child mortality has also fallen drastically. On the other hand, many so-called civilization diseases occur today in old age, which can be traced back to an unhealthy lifestyle such as overeating , lack of exercise or smoking. However, medical progress has already reached the point where the number of deaths from these diseases is greatly reduced. This also increases the general life expectancy.

The greatest risks of dying early today are such factors as obesity ( adiposity ), smoking, lack of exercise, high blood pressure or diabetes . There are also genetic factors that influence life expectancy.

Gender differences were also found. Statistically, men die earlier than women. This can have many causes. For example, men often take greater risks and suffer more accidents than women as a result. Men are more frequently exposed to higher risks at work than women and accordingly often fall ill with occupational diseases. In addition, until recently, men were less aware of their health than women.

Biological factors may also play a role in the difference in life expectancy between the sexes. Hormonal and genetic causes are discussed. The male sex hormone is said to promote the development of arteriosclerosis and thrombosis , for example .

Also, males only have one X chromosome , while the Y chromosome only carries sex-related information. e.g. B. Genetic errors on the genes of the X chromosome, they can not be compensated by a second X chromosome. The resulting diseases may shorten the life expectancy of many men.

Diseases & Ailments

However, an increase in life expectancy does not automatically mean an increase in the quality of life. Although many illnesses no longer lead to immediate death, the likelihood of developing chronic illnesses increases with age. 

These diseases often drastically reduce the quality of life. Rheumatic diseases often develop, for example , which are accompanied by restricted mobility. Chronic cardiovascular diseases are also common . In many cases, dementia also develops in old age .

The cost of care increases in parallel with the increase in life expectancy. In the coming years, medicine will therefore face the growing challenge of treating these so-called degenerative diseases in such a way that the quality of life is maintained or restored.

There are already several indications for this. With regard to Alzheimer ‘s disease , there are promising approaches for the development of an active substance that can at least stop the disease. However, much research work is still needed in this area.

Significant progress has also been made in controlling cardiovascular diseases, for example through the introduction of new cardiac pacemakers . In principle, medical progress will make it possible to achieve significant therapeutic success in all age-related diseases. However, not only medicine, but also the change in health awareness must contribute to maintaining the quality of life by avoiding age-related diseases in addition to increasing life expectancy.

Lisa Newlon
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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.