Numbers Game

The phrase “you’re only as old as you feel” has a whole new meaning now thanks to the world of biological age tests. But what do these buzzy tools really tell you about your wellness and habits? Read on.…

- Kristine Thomason

In 2021, I mailed five pipettes of my blood to a lab. According to the results, my "biological age" was 17 years old. The odd part? I'd just celebrated my 29th birthday.

For context, I was simply curious to know more about my health status. Perhaps that was because of my job as a wellness writer, or the fact that while I do a lot to support my overall well-being (eating a plant-heavy diet, regular long hikes and runs, quality time with good friends, etc.), I'm also chronically stressed out. I wanted to know if my insides reflect my habits, so to speak.

While chronological age is based on the number of years you've been alive, biological age tells a slightly different story. There's no single definition of it, but the idea is that you can measure how your body is aging on a cellular, physiological level (which means the resulting number may not match your years on earth!).

My initial reaction to the test results: Wow, I guess I'm on the right track. Then my skepticism Can that number actually be true? Is there any legitimacy to this? Bio age tests like the one I took have soared in popularity recently, leading experts to ask similar questions. Spoiler: Biological age *is* a legit concept that's rooted in science, but the notion of quantifying it with an at-home test is still speculative.

The Basics