Saturday, September 21, 2024

Older by Steps

We tend to think of aging as a simple line graph. On the bottom is the calendar, one tick for every New Year's Day. On the left side is our age, a marker for each year we are above ground. It starts in the bottom left corner on the day we are born, and with a little bit of luck, ends somewhere in the top right eighty or ninety years later. It's a steady progression come hell or high water, one up, one over, a pattern that no one has ever figured out how to change.

On the other hand, we generally look at our health and the aging process as the exact opposite. That graph has the same left axis of years we are alive, but with your birthday at the top. Meanwhile, the bottom ticks represent our overall health from good to, well, less so. That line starts in the top left when we are born, when all systems are hopefully "go" and functioning perfectly. As the years click by that line steadily descends as things start to not work so well: a knee, a shoulder, your stomach, your teeth. The reasons vary, from an injury received, to the fallout from a bug or disease, to just normal wear and tear. Only one thing is for sure: the overall direction doesn't change, and both graphs reach their final points at the same time.

Every person has a slightly different trajectory, zigging here and zagging there. That means that your aging plot line is hardly as straight as its calendar sibling, nor the same as your neighbor's. But according to a recent study we actually all align at two major inflection points in our lives. These changes happen to every person at a molecular level, regardless of our overall health. Scientists at Stanford published a study in the journal "Nature Aging" that shows that humans get suddenly older around age 44, and then again around age 60.

The researchers followed 108 participants over several years, conducting a range of tests and collecting multiple samples of biological materials. They also kept track of each person's personal microbiome, charting their RNA, proteins and metabolites, the end results of the body breaking down food, drugs or other chemicals. All together they amassed over 250 billion distinct data points from which to draw their conclusions. Even adjusting for women in the sample experiencing menopause and its effects, the data showed no discernible difference between males and females, nor by race. It seems that we just have a sharp increase in molecular changes at middle age, and then again before social security kicks in. 

As to whether these changes are driven by biological alterations, behavioral ones or a mixture of both, the jury is still out. However, evidence points to the influence of at least some external factors. For example, the mid-40 cohort correlates with raising families and the stress that causes, which can also result in an increased use in alcohol, poor diet and reduced sleep, all factors which have been previously linked to age-related illnesses. In other words, your teenager might scientifically be causing you to get older. 

With that in mind, one wonders if the scientists shouldn't broaden their criteria and look for similar matches along the way. There are plenty of other inflection points that certainly seem to age us in spurts. Middle school takes a toll, not to mention freshman year of college. Your first job interview can wreak havoc, as does your first apartment. Marriage, first child, a dog: check, check, check. Unless your name is Dorian Gray or Benjamin Button, each of those inflection points adds (or subtracts depending on your outlook) a few years in physical, emotional and psychological wear and tear. Our aging graph starts to look less like a line, and more like, with apologies to Led Zeppelin, a stairway from heaven. 

Speaking from my own experience, I can certainly say that my personal graph moves in fits and starts, some days with way more starts. Being a sample of one, I hesitate to draw any widespread conclusions. But I can't be the only person who thought "this is gonna take years off my life" at multiple points along the way. I may have been pulling my hair out; I didn't know I was corrupting my molecules as well.

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Marc Wollin of Bedford feels older every day, some days more than others. His column appears weekly via email and online http://www.glancingaskance.blogspot.com/ and https://marcwollin.substack.com/, as well as via Facebook, LinkedIn and Twitter.


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