[Science Solitaire] How old are you? It’s complicated.

All of us have had our birthdays pass at least once during this pandemic. Being at home for such a prolonged period with limited company has made many of us more keenly aware of our bodies and minds, our overall health.

Did you feel a lot older than just the year that passed when you marked your birthday? We feel the passing of the years in the diminished capacities of our bodies compared to our youth. But why do people of the same age, with more or less the same physical state, differ in the number of years they live?  

This is because the “number of years” is scientifically a measure of aging, but it is not the only one. “Aging” is not equal to the number of years you have lived. “How old are you?” should really be changed to “How many years have you been surviving?” because the number of years (chronological age) you have lived is not a reliable indicator of how old you really are.  I can think of at least 3 observable/scientifically grounded reasons for this.

One is because being “older” can mean a couple of things, mentally. One of them is the higher likelihood that the older you are, the more mature you will be, which is a good thing. The impulsiveness of teenagers puts them at high risk for death at that stage in their lives, and that is a scientific fact. But some young people mature early, in the sense that they gain control over their emotions earlier.

So when you are asked how old you are, it does not really say anything about the level of your emotional courage or range. In this sense, if being “older” means having more emotional control, then I would rather be “old” when it comes to this aspect.

But being “old” could also mean the less likely one is excited to learn new stuff and be open-minded. In that sense, I would like to still try harder to learn and be open and thus be “young,” even if I have already accumulated over 50 years. There are also some infamous personalities who are famous for just having lived long. They give us very good reasons to want our lives to be more than long.

The second reason has to do with the fact that while you carry around one body, including one head, your various organs/bodily systems age differently. I wrote about this at length in a 2020 column. So far, science has identified liver, kidney, metabolic, and immune clocks or calendars. How each of these organs/systems age contributes to how old you really are. So finding out which organ/system grows older, in terms of its vulnerabilities, including its genetic ones, farther than the rest, will help you protect it early and also not abuse it.

The third reason has to do with new research that it is not even only about the physiological markers that make for one’s age, but also how old we really feel, i.e. your psychological age. This is not as simple as just sensing your overall mood for the day and based on that, judge yourself how old you are. It has to do with all your ups, downs, and in-betweens, and how, once they are recorded, form a baseline to which you go back.

The summary is that how young or old you feel you are – your “subjective age” – is a greater predictor of overall “age” than chronological years. In that sense, the saying “You are as old as you think” is true. You can go to this beta site where you can find out your own subjective age. 

“Psychological age” is striking because it embraces positive thinking – including enjoying the company of others, which is a much stronger predictor of longevity than the biomarkers of reason number 2. Also, feeling and being “sexier” nuances your age so that you become younger than your chronological age.

Also, related research was done during COVID times that found that older adults registered as even older in their psychological age because of the severe social limitations, as they also experienced malnutrition and loneliness. 

This growing body of research proves that “age” is really largely how you perceive your own life as you live it, and is not an external flow of the years that you are helpless to shape. This means that even in pandemic times, we should pay as much attention to how we feel about ourselves and how we can help others about how they feel about theirs, as we do about vaccines. 

How old are you? It’s complicated. It is not only the number of years you have been around but much more: how you feel about having been around, no matter how long or short. You can shape that. And that is the good news. – Rappler.com

Maria Isabel Garcia is a science writer. She has written two books, "Science Solitaire" and "Twenty One Grams of Spirit and Seven Ounces of Desire." You can reach her at sciencesolitaire@gmail.com.