To the average layman, aging is often seen as a steady progression. However, a new study from Stanford University has found that there are, on average, acceleration in the aging process around the ages of 44 and the early 60s due to molecular changes.
Researchers say the human body does not age at a constant rate throughout adulthood as we thought. Instead, it accelerates dramatically around ages 44 and 60.
This type of aging research focuses on tracking “biological age,” which refers to changes that occur in the body over a lifetime, affecting proteins, metabolites and gene activity. This concept is distinct from the “chronological age” that people celebrate each year on their birthdays.
The study examined 108 participants who donated blood and other biological material over the course of years.
The new study from Stanford University—inspired by the observation that risks for things like Alzheimer’s diseases rise sharply with old age—claims that humans actually age in a much less linear fashion than we believed.
The scientists examined thousands of different molecules—specifically, the micro-universe of bacteria, fungi, and viruses that live within us and on our skin—in subjects between the ages of 25 and 75. The team found that the numbers of these various molecules changed drastically around two specific ages on average.
“We’re not just changing gradually over time; there are some really dramatic changes,” Stanford University’s Michael Snyder, a professor of genetics and the study’s senior author, said in a Press statement. “It turns out the mid-40s is a time of dramatic change, as is the early 60s. And that’s true no matter what class of molecules you look at.”
To come to these groundbreaking conclusions, the aging experts looked at sample molecules, microorganisms, and gut and skin microbiomes from 100 people between the ages of 25 and 75.
Collected routinely every three to six months for up to seven years, these samples indicated upon analysis that rather than gradual, chronological shifts occurring over time, there tended to be two periods of rapid change in microbes and microorganisms around the ages of 44 and 60.
As the researchers found, there seemed to be some “dysregulation” when it comes to skin and muscle stability during both age crests of molecular and microbial changes. Those findings appear to suggest that during both those age waves, skin, and muscles age more rapidly.
Beyond those surface-level aspects that occur during both shift crests, the research also found that each wave seemed to accelerate specific kinds of changes, too.
Specifically, molecular changes related to the way we metabolize alcohol and caffeine occur around age 44. At 60, meanwhile, changes occurred in the immune system and kidney functioning of the subjects.
Specifically, decreasing alcohol consumption and learning exercises that protect your heart and increase muscle mass could benefit people as they keep these aging crests in mind, the Stanford scientists said.
At the end of the day, that’s probably good advice for everyone, regardless of their age.
Finding that biological aging accelerates at two points in midlife could help researchers understand why the risk of certain illnesses increases in fits and starts as chronological age rises.
For example, approximately 6.5% of people ages 40 to 59 have coronary artery disease, but the prevalence rises sharply to 19.8% in people ages 60 to 79.
Obviously, scientists need to do plenty more research to test out this hypothesis, and the authors noted that there are certainly lifestyle factors that could both result in these changes and help ease the worst of them, too.
