While we celebrate our birthdays annually, marking our chronological age, this doesn’t always align with how quickly our bodies are aging biologically. Scientists have identified 10 distinct blood markers to help distinguish between the two.
Although numerous methods exist to assess biological age, there is a demand for tests that are both more accurate and easier to conduct. A blood test that identifies specific biomarkers could meet these criteria.
A team from the University of Konstanz in Germany has led this research, aiming to enhance our comprehension of biological aging and potentially serve as a warning system for age-related disease risks through a new blood-scanning technique.
“The biological aging process is very complex,” says biologist Maria Moreno-Villanueva from the University of Konstanz. “It affects all of the body’s tissues and organs, and it is not the result of a single cause.”
“As a result, single biomarkers are not enough to reliably determine a person’s biological age. On top of this, there are also differences in how men and women age.”
The researchers initially measured 362 different parameters in blood samples from 3,300 individuals, aged 35 to 74. Through statistical modeling and machine learning, they narrowed these down to the 10 most significant biomarkers, with separate sets for males and females.
This selection process involved comparing each biomarker, which included chemical, genetic, cellular, and molecular signaling, against chronological age. The combinations most accurately predicting age were selected.
This resulted in predictors that illustrate how a person’s blood typically appears at specific chronological ages. Discrepancies between a person’s blood ‘age rating’ and their actual age indicate either slower or faster biological aging.
To test the biomarkers’ validity, researchers analyzed blood samples from groups known to age biologically at different rates: individuals with Down Syndrome (also known as trisomy 21), smokers, and women undergoing hormone therapy.
The blood tests successfully identified the expected changes in biological aging—either accelerated or decelerated—demonstrating that the biomarkers were interpreted accurately.
“Against the backdrop of current research on the aging effects of smoking, hormone replacement therapy, or trisomy 21, all of these results are plausible and confirm the validity of our bioage score,” says molecular toxicologist Alexander Bürkle, from the University of Konstanz.
The study also revealed that certain selected biomarkers may drive biological aging, while others simply indicate it. This distinction could offer more detailed insights into an individual’s health through a blood test. Biological aging serves as a valuable measure of fitness and well-being, with a ‘younger’ biological age typically linked to better health and longevity.
The researchers believe the new test could be applied in numerous contexts, from assessing health to evaluating the success of treatments aimed at preventing age-related illnesses.
With the global population increasingly aging, researchers are striving to ensure that extended lifespans are also healthier. A deeper understanding of biological aging and its influencing factors will be crucial in achieving this goal.
Related: The Blood of Centenarians Reveals 37 Proteins Linked With Slower Aging
“If we look at the bioage scores of a lot of people born in the same year, we see a wide range of values,” says Morena-Villanueva. “This shows very clearly that each person has their own individual biological aging process and, for example, that some people are significantly younger biologically than their chronological age would seem to indicate.”
The research has been published in Aging Cell.
