When it comes to biological aging, it seems that the body changes gears three times in our lifetime, as 2019 research suggests: key thresholds are 34, 60, and 78 years.
In other words, there is evidence that aging is not a long, continuous process that moves at the same rate throughout our lives.
The findings can help us understand more about how our bodies begin to break down as we age, and how age-specific diseases, including Alzheimer’s or cardiovascular disease, can be better addressed.
The same study has also proposed a new way to reliably predict people’s age using protein levels (the proteome) in the blood.
“By deep extracting the aged plasma proteome, we identified undulating changes during human life,” the researchers wrote in their paper, published in December 2019.
“These changes were the result of groups of proteins moving in different patterns, culminating in the appearance of three waves of aging.”
The team analyzed data from the blood plasma of 4,263 people aged 18 to 95, examining the levels of some 3,000 different proteins that moved through these biological systems and acted as a snapshot of what was happening in the body: d ‘them, 1,379 to vary according to age.
Although these protein levels often remain relatively constant, the researchers found that there were large changes in readings of various proteins around young adulthood (34 years), late middle age (60 years), and old age. (78 years old).
Why and how this is happening is still unclear; but if proteins can be traced to their sources, it could allow a doctor, for example, to warn you that your liver is aging faster than the average person’s.
It also emphasizes the link between aging and blood, which has been seen in previous studies.
“We’ve known for a long time that measuring certain proteins in the blood can provide you with information about a person’s health status: lipoproteins for cardiovascular health, for example,” said neurologist Tony Wyss-Coray. of the Stanford Alzheimer’s Disease Research Center (ADRC) at the time.
“But it hasn’t been appreciated that the levels of so many different proteins, about a third of all we’ve seen, change markedly as we age.”
The researchers were able to establish a system by which the mixture of 373 selected proteins in the blood could be used to accurately predict someone’s age, in about three years.
Interestingly, when the system failed to predict too young an age, the subject used to be very healthy for his age.
Another finding from the study gives more evidence of something that was already suspected: men and women are a different age. Of the 1,379 proteins that changed with age, 895 (almost two-thirds) were significantly more predictive for one sex compared to the other.
These are still the first findings (researchers say any clinical application can still have five or ten years of rest) and much more work will be needed to find out how all of these proteins are markers for aging and whether or not they actually contribute. to this.
However, it raises the possibility that one day you will have a blood test that can measure your aging, at least at the cellular level.
And the more we know about aging, the more we can do to counteract it. This could report everything from knowing what to drink and eat to potentially add a couple of years of life to identifying treatments to avoid some of the worst age-related conditions.
“Ideally, you’d like to know how it affects pretty much anything you’ve taken or did at your physiological age,” Wyss-Coray said.
The research was published in Nature medicine.
A version of this article was first published in December 2019.