Biological Evidence Of The Life Expectancy Limit In Human Aging
For a long time, scientists have been trying to figure out if there’s a natural ceiling to how long humans can live. It’s tricky because as more people live to be very old, the data gets a bit messy. However, new research has shed light on this mystery by looking at the fundamental building blocks of our bodies: our cells.
The study used a special mathematical tool, called a logistic function, which takes into account how much energy our cells have. Think of cellular energy as the fuel that keeps all our body’s processes running smoothly. As we age, this fuel naturally starts to run low, a process called cellular energy depletion. This depletion plays a crucial role in how long we can live.
By applying this model to real-world data, particularly from populations with very long lifespans, researchers were able to identify a maximum biological lifespan, which is the absolute longest a human could potentially live, estimated to be around 105 years. Based on this, they also calculated an achievable upper limit for average life expectancy at birth, suggesting it’s around 98 years. This means that while more people are living longer, there appears to be a biological boundary. The research also showed that as we approach this limit, the survival rate trajectory becomes “rectangular,” meaning that most people would live to a similar old age before a rapid decline, rather than a gradual decrease in survival across many ages. This work highlights the critical role of cellular energy in determining our longevity.
Source: link to paper