Understanding the different periods we go through throughout life is a simple, yet complex task at the same time. It is simple because the changes that take place in our body are in plain sight: the body increases in size proportionally to the passage of time (until adulthood) and cerebral development implies that we become more conscious and independent in the activities we perform everyday. But it is complex to understand mechanisms like learning, the formation of memory and even a process science has not yet resolved: the aging process.
Life expectancy is a demographic indicator that estimates how many years, averagely, a group of men and women will live. It not only depends on each person’s physical conditions, but also on their habits (healthy diet, physical activity, being a non-smoker, among other things) and the hygienic and health conditions of the place they live in. This way, the improvement of countries’ quality of life, advances in medicine and in health policies have increased life expectancy. In prior centuries it was very low because there were no vaccines or sterilization of instruments, nor was there a cure for many diseases that pose no vital risk nowadays. Today, only considering developed or developing countries, we can state that life expectancy is over 70 years old; women live longer compared to men.