If you’re someone who feels younger than the age listed on your driver’s licence, new research suggests it might not just be in your head.
According to a recent report by CNN, experts at Yale Medical School say humans have two ages: a chronological age, your age based on when you were born, and a phenotypic or biological age, which is the age at which your body functions.
In other words, you can be 80 years old but have the health of a 65-year-old.
“In my lab, we work on a lot of different types of aging measures,” Yale professor and researcher Morgan Levine told CNN. “One of the most recent ones is based on blood measures you get at your normal doctor’s appointment. We basically take those and combine them using different algorithms to get what we call someone’s phenotypic age, or biological age.”
Levine explained that this testing reveals how your body functions compared to average fitness or health levels for your age.
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Dr. Michelle Silver, an assistant professor at the University of Toronto and author of Retirement and Its Discontents: Why We Won’t Stop Working, Even if We Can, agrees that people can have a biological age that differs from their actual age.
“In adulthood, chronological age is really good at predicting your next birthday and a few health issues,” she told Global News. “But there is great variability across adults, particularly when it comes to physical, functional abilities.
“In my work, I’ve seen retired Olympic athletes in their 70s whose dexterity and ability to move is more like a 20-year-old and others who stopped exercising completely when they stepped down from the podium, so at 50 their biological age was likely much closer to an 80-year-old.”
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How can you determine your biological age?
The researchers out of Yale have identified “nine biomarkers taken in a simple blood test that seemed to be the most influential on lifespan,” CNN reported. These include blood sugar, kidney and liver measures, and immune and inflammatory measures.
The team then enters a person’s data into a computer and an algorithm determines their biological age. Levine said that folks with a biological age lower than their actual age have a lower mortality risk, whereas people who have older biological ages are more at risk for health problems and developing diseases.
On top of physical risks, Silver said if someone’s biological age is greater than their actual age, it can affect their mental well-being, too.
What affects how you age?
So if the key to living longer is a lower biological age, what factors affect your ability to hold onto youth?
Silver said factors like genetics, the environment in which you live, your lifestyle, diet and exercise habits all play a part in how you age. She pointed out that stress also impacts aging, as chronic stress can lead to an increased risk of disease and mental health issues.
“To be physically active and socially engaged at later stages in the life course can affect how we age,” Silver added.
How to “slow down” aging
The good thing about biological age is that it can often be changed.
“Lifestyle definitely plays a role in aging,” Silver said. “Factors like what you eat and how often you move on a daily or even hourly basis matter at every stage of the life course.”
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Silver acknowledged that the older we get, the more challenging movement can be. Despite this, she said people should create opportunities to be physically active to whatever extent is possible.
“For most of us, sitting at a desk for most of adulthood is not good for the aging process,” she said.
And while physical movement is key, mental and social engagement also helps “slow down” bodily decline. Silver said seeing others and maintaining relationships is important, just as staying up-to-date with reading or listening to the news helps keep us sharp.
“Maybe join a book club, too.”