- Chronological age refers to how many years we have been alive, while biological age is how old your cells and organs are.
- Experts suggest that the biological age of the whole person, or of individual organs, is a better indicator of health and aging than chronological age.
- Now, a study has found that a blood test that detects the biological age of organs can predict the risk of health conditions developing many years later.
- The researchers suggest that this type of test could be crucial in helping to predict and prevent many diseases, including heart disease and some cancers.
Researchers think about a person’s age in two different ways:
- chronological age is the number of years since a person’s birth and is the age a person identifies with
- biological age is a measure of how old the cells and organs are, and it can vary widely from a person’s chronological age, depending on their genetics and lifestyle.
Biological age can also vary within a person, with some organs biologically older than others.
Chronological aging is linear, and cannot be accelerated or delayed. However, biological aging may be faster or slower than chronological aging, depending on genetics and environmental factors.
The difference between the two measures is often referred to as an age gap. A negative age gap, with biological age less than chronological age, represents healthy or delayed aging, whereas a positive age gap indicates that a person is aging faster than expected.
Now, a team led by researchers at University College London in the United kingdom has found that a blood test to detect the biological age of organs can predict the risk of health conditions years, or even decades later.
Their study, published in
Cheng-Han Chen, MD, a board-certified interventional cardiologist and medical director of the Structural Heart Program at MemorialCare Saddleback Medical Center in Laguna Hills, CA, who was not involved in this research, explained for Medical News Today that
“This long-term observational study found an association between ‘organ age’ as assessed by the level of various proteins in the blood, and future risk of developing different diseases. This type of analysis could potentially provide a method of risk stratification in order to help address and hopefully modify someone’s chance of developing a certain disease.”
The researchers recruited 6,235 adults from the Whitehall II study of U.K. government employees. They assessed their health from electronic health records at baseline and at follow up 20 years later.
All participants gave blood samples between April 1997 and January 1999, when they were aged between 45 and 69 years old. Researchers then carried out
From these protein data, they identified age gaps in nine different organs or organ systems — the arteries, brain, heart, immune system, intestine, kidney, live, lung, and pancreas — as well as for the whole person.
Using these data, the researchers then looked at 45 age-related diseases, to determine whether age gaps in any organs affected the risk of developing these diseases.
They noted that biological aging progressed at varying rates in different organs within the same individual, and that individuals with any fast-aging organ faced an increased risk of 30 out of the 45 age-related diseases examined.
Individuals who had larger organ age gaps were at risk for developing diseases later in life. For example, a higher heart-age gap was linked with a higher risk of heart disease later in life.
However, the researchers also found that advanced aging in a specific organ increased the risk of multi organ illnesses, and that rapid aging in more than one organ increased the risk of disease in a single organ. And the effects of cellular aging were widespread, with faster-aging organs associated with greater mortality.
Jagdish Khubchandani, PhD, professor of public health at New Mexico State University, noot involved in this study, explained how organs might affect each other.
“For me, the most interesting finding was on how aging of one organ affects disease probability and aging of other organs,“ he told MNT.
“It makes some sense as these organ functions affect each other,“ Khubchandani added. “Also, there are shared immune, genetic, vascular, and inflammatory mechanisms. But, from a practice standpoint, these interrelationships will make preventive practice and therapy development challenging. Still, this was a much needed investigation with many novel findings.”
Age gaps observed within the immune system were strongly associated with later development of dementia, and a rapidly aging intestine was the strongest risk factor for Parkinson’s disease.
These findings reinforce earlier studies that have linked inflammatory markers in the blood with higher dementia risk, and a
“The study interestingly found an association between proteins associated with inflammation, and future risk of dementia. This suggests a relationship between inflammatory processes and neurodegenerative disorders, something that should be the subject of further research.”
– Cheng-Han Chen, MD
Speaking to MNT, Sebnem Unluisler, Chief Longevity Officer and Genetic Engineer at the London Regenerative Institute in the U.K., who was likewise not involved in this research, noted that:
“This type of blood test could be a game-changer in preventive medicine, particularly in longevity-focused Healthcare. By identifying organ-specific aging early, clinicians could implement targeted interventions — such as lifestyle modifications, medications, or regenerative therapies — before disease manifests.”
The study authors also emphasize that their research has limitations. As an observational study, it cannot prove causation, the cohort was, on the whole, healthier than the general population, and incidence rates of some diseases were low, so it was hard to confirm associations.
Although tests like this could have great potential, there are issues to be overcome, as both Unluisler and Khubchandani told us.
“While promising, this test will need further validation and standardization before clinical implementation. Additionally, ethical considerations arise regarding how to counsel patients who learn their organs are aging prematurely — particularly in cases where interventions are limited. Nonetheless, this study highlights the growing potential of proteomics in longevity medicine and precision healthcare,” Unluisler said.
“The challenge is that aging has many markers with varying predictive abilities for mortality and morbidity. Another challenge is how widely these markers can be utilized by clinicians and be available for the general public to get their risk profiles measured (e.g. cost and access). Finally, while these developments in markers can help with precision medicine and newer medications, change in individual behaviors will also be required.”
– Jagdish Khubchandani, PhD
