Lifespan can be predicted by blood — a discovery that changes everything.
Sometimes it seems that lifespan is determined by genes, lifestyle, or simply luck. Scientists had already found that blood tests can show the chances of a long life, but new research has revealed that our blood contains molecules that can predict the future more accurately than age. These are tiny RNA fragments that were previously largely overlooked. Researchers discovered that their levels are linked to whether a person will live for several more years. Moreover, this works better than many medical tests. And the most surprising finding — age turned out to be not as important as commonly believed.
Which Blood Molecules Are Linked to Lifespan
The study, led by Virginia Byers Kraus from the Duke University School of Medicine, included 1,271 people over the age of 71. Scientists analyzed blood samples and searched for molecular markers that could be associated with lifespan.
The key discovery was piRNA (PIWI-interacting RNA) — very small fragments of genetic material that were previously thought to be important only for reproductive cells. It turned out that they are also present in blood and may reflect aging processes.
When researchers compared the data, an unexpected finding emerged: people who lived longer had lower levels of nine specific piRNAs. This contradicts conventional thinking, as these molecules were believed to protect cells.
After adding molecular markers, age almost ceased to play a role. In other words, biological age turned out to be more important than the number on a passport.
Age alone proved weaker than molecular markers: several piRNAs in blood plasma accurately predicted two-year survival in elderly people.
Why Age Doesn’t Reflect the True State of the Body
Scientists tested hundreds of indicators — a total of 828 small RNA molecules were measured. Participants were then divided into groups to avoid statistical errors, and a predictive model was built. The result was unexpected:
- the age-based model worked almost like random guessing
- the molecular marker model provided a much more accurate prediction
- a combination of molecules and health status performed no worse than complex medical systems
The model that accounted for the following indicators worked especially well. This scheme predicted two-year survival more accurately than most clinical methods.
- five piRNA molecules
- physical condition of the person
- level of “good” cholesterol
Can We Extend Life by Influencing Aging Molecules
The most intriguing part of the study is the possibility of influencing these indicators.
Statistical modeling showed that if piRNA levels in at-risk individuals were brought to the levels of long-lived people, the probability of living another two years could nearly double. These are still just calculations, but they align with results from animal experiments. For example:
- in roundworms, disabling the small RNA system doubled lifespan
- in fruit flies, similar changes also extended life
Researchers emphasize that this does not mean a drug will appear soon. But piRNAs could become a new target for aging therapy. And this direction is currently being actively studied. For now, such tests are not used in routine medicine. The study results need to be confirmed on other samples, in other age groups, on different platforms, and over longer time horizons than two years.
But the study demonstrates an important point: biological age can differ significantly from calendar age, and it is biological age that determines how long we will live.
