Scientists have determined a potential ultimate limit for the human lifespan, suggesting that individuals could live to an average of 190 years if other aging processes were overcome.
The research, conducted by scientists at the Skolkovo Institute of Science and Technology, focused on the role of somatic mutations – random errors that accumulate in DNA with each cell division – as the primary factor limiting human longevity.
Even if all other hallmarks of aging, such as telomere shortening and cellular waste buildup, were successfully treated, these somatic mutations would continue to degrade the body's ability to function, eventually leading to organ failure. This process imposes a theoretical maximum on how long a person can live.
"What would be the lifespan of a human who has overcome all ageing mechanisms except somatic mutations?" asked lead author Dr. Dmitrii Kriukov. "We built a model of human ageing driven solely by somatic mutations. Our model estimates how this process alone affects lifespan by slowly depleting cells across tissues."
The model estimates that if medicine could address all aging factors except somatic mutations, average lifespans could range between 146 and 194 years. This is roughly double the current average life expectancy in countries like the UK.
However, the researchers also noted a theoretical maximum lifespan of up to 627 years, though this scenario is based on extreme theoretical limits.
The study highlights that while somatic mutations are a relatively weak driver of aging on their own, their cumulative effect becomes critical when combined with other aging mechanisms. The researchers suggest that certain tissues, like those in the heart and brain, are more susceptible to accumulated mutations because their cells are largely irreplaceable, unlike those in the skin or liver which can be replenished.
These findings may challenge the pursuit of immortality by some scientists and entrepreneurs. Efforts to extend lifespan through treatments like partial human 'de-aging,' being investigated in clinical trials, or radical anti-aging regimens costing millions annually, may ultimately face the fundamental biological limit imposed by somatic mutations.
