Human Life Expectancy

Do you know how many years a human can live? Many scientists from diverse fields have attempted to answer this question recently because human life expectancy has increased approximately 30 years in the last century. Humans could live around 30 to 40 year in the eighteenth and nineteenth centuries. At that time, mortality rates were the highest in recent human history. Later, human life expectancy incremented incredibly during the twentieth century; as a result of the development of medical science, specifically antibiotics and vaccines.

The United States Central Intelligence Agency reported that the average of human life expectancy was approximately 72 years in 2015. On one hand, the highest human life expectancy prevailed in Monaco, Japan, and Singapore: 89.5, 84.7, and 84.7 respectively. On the other hand, the lowest human life expectancy was observed in Afghanistan, Guinea-Bissau, and Chad: around 50 years in all these countries.

The gap between the highest and lowest human life expectancy is around 40 years. In other words, the difference is equal to human life expectancy during the nineteenth century. Humans can live longer nowadays, but gaps between countries are huge. However, humans are living longer. In that context, some researchers ask about limits of human life. There are three different perspectives to try to estimate the maximum life span.

First of all, the mathematical perspective expresses that humans can live around 126 years. That number is a result of estimation according to the Weibull model which is a measurement of machines efficiency. Nevertheless, the best function that matches human life expectancy (over 70 years old) is a quadratic function because mortality increases linearly in the top ages. As a result, mortality rates are high at the beginning and end of human life.

Second, some biologists have affirmed that humans have a maximum life span of around 125 years. This data corresponds to the resistance of body cells. So the aging process depends on cell aging. For that reason, most of the chronic diseases are developed in the elderly, such as malignant neoplasms, respiratory illnesses, and cardiovascular diseases. All of them are associated with cell function deterioration.

Third, biotechnological engineering affirms that it is possible to extend human life because technology allows us to redesign the human body. Therefore, humans have increased their life expectancy by more than 30 years in the current century. As a result, humans could live around 150 years or more.

The discussion about the human life expectancy is extensive. In fact, humans are living longer than past generations. However, cell deterioration is an interesting proposal for future studies because health quality is one of the most important factors about human life expectancy, and it has a strong association with studies of cell weakening. Nowadays, it is a fact that humans can live longer, but if elder people could live longer, what might be the general living conditions of this population group?