How long can a human being really live? What if the answer didn’t just depend on a balanced diet, regular physical activity or meditation? A study published in 2021 in the journal Nature Communications by the biotechnology company Gero puts forward another avenue: the real limit of our longevity could be hidden in our ability to recover after daily challenges.
How do researchers measure physiological resilience?
To do this, researchers have developed an indicator called “Dynamic Organism State Indicator” (DOSI). Concretely, they analyzed blood counts (CBC) taken in more than 540,000 volunteers. They then crossed this data with the variations in activity recorded by connected watches in more than 4,500 participants, notably from the American NHANES study.
Their observations show that with age, variations in DOSI become greater and that the time required to return to a normal state after stress lengthens. The media Science et Vie explains that it takes around two weeks at 40 years old to fully recover, compared to almost six weeks at 80 years old. In other words, this famous “spring” takes more and more time to return to its initial shape.
A limit between 120 and 150 years?
By extending their models, the researchers arrive at a critical zone of between 120 and 150 years. Beyond this age, physiological resilience tends towards zero. The slightest disturbance could then be enough to unbalance the body, even in the absence of a particular illness.
According to an article published by the European Union information service CORDIS, diseases linked to aging would then no longer be the primary cause of death, but rather the factor which precipitates an organism which has already become extremely fragile.
However, these conclusions must be interpreted with caution. A specialist interviewed by the media Science et Vie recalls that this work “suggest, but do not prove” the existence of a strict biological limit to human lifespan. For its part, the National Institute of Demographic Studies (INED) emphasizes that certain models highlight a plateau in mortality after 105 years, a phenomenon which continues to fuel scientific debates.
Why this discovery concerns us all
Physiological resilience is neither a matter of willpower nor positive thinking. It is a biological, measurable mechanism, even if the tools to evaluate it are still under development. Researchers now hope to better understand why some people age in better health than others, and to identify the levers capable of preserving this essential ability to recover over the years.