By Dr. Kaycee Reyes
What is aging?
Aside from the passage of time, aging can also be described as the process of growing older, or what others have defined as senescence, or a gradual decline of the biological function of living things. One day you’re a child—young, strong, and healthy, and the next thing you know, you’re more prone to sickness, you walk slower, your hair is gray, and your skin is wrinkled. While it is inevitable that all humans will grow older, get old, and pass away, as is the cycle of life, have you ever asked yourself why we get old? Why can’t we stay young? Why can’t humans live forever? Well, science might have the answer.
Almost 200 years ago, in 1825, British actuary William Gompertz first hypothesized that a human’s probability of dying increases exponentially as one gets older; specifically, Gompertz states that the probability of death doubles every eight years, so that that if there is a one in 3,000 chance for a 25-year-old to die, it will become a one in 1,500 chance by the time he’s 33, and so on. This excludes the fact of any individual getting into an accident or having a disease, as this theory holds true across many countries, cultures, and decades, so much so that regardless of an uncontrollable event, this theory may prove that humans are naturally incapable of immortality. Then in 1859, English naturalist Charles Darwin, one of the most well-known among all theorists on evolution, stated in his paper that all organisms develop and inherit the qualities that will make them live longer, survive, and reproduce. It still raised questions, however, as to the continuous occurrence of diseases and aging, instead of living forever.
Another theory of aging and longevity is the Programmed Death Theory by German environmental biologist August Weismann who, in 1882, said that all animals have an end to their lifespan, and that older animals have to give way to younger animals that need more resources like space and food, which is the reason for their death. But then, not all animals live to old age, which raises questions about this theory as well.
More acceptable current theories that are being studied are the Mutation Acceleration Theory (1952) by British zoology and anatomy and Nobel Peace Prize winner in medicine Sir Peter Medawar and the Antagonistic Pleitropy Theory (1957) by American university professor George Williams. Both theories generally state that aging is a natural cause by the increasing adverse effects of diseases as one ages (Medawar) and that a single gene can have more than one trait that can positively affect an individual in his youth but may adversely affect him as he gets older (Williams).
All of these theories point to one thing: that an organism’s life span can be prolonged, but death still is inevitable.
Science has always been fascinated about life, how organisms work, and why they die. Even nowadays, technology finds ways to extend the human lifespan, coming up with new cures to diseases, more convenient ways to live, and finding ways to have better nutrition. No matter how far we have come in terms of life expectancy, however, one can still not live forever. We can only improve our quality of life and, to many, that is always more important than living longer.