News · Longevity & Aging
Fix everything but DNA damage and you get 156 years
A modelling study in npj Aging asked what human lifespan would be if every driver of aging were solved except mutations building up inside cells. The answer was around 156 years, and the bottleneck was the cells the body cannot replace.
Based on a peer-reviewed computational modelling study in npj Aging
- A computational model, not an observation: no person in it is real and nobody lived 156 years.
- Removing every aging driver except cell mutations still capped median lifespan at 156 years.
- The theoretical no-aging baseline the model starts from is 1,759 years.
- Neurons and heart muscle are the bottleneck; the liver stayed functional for thousands of years.
- Across all organs the estimate lands at 146 to 194 years, about twice current human longevity.
Ask how long a human could live and you get either science fiction or a shrug. A modelling study in npj Aging tries a more disciplined version of the question: take one specific cause of aging, assume every other cause has been solved, and calculate what that one cause alone would still cost you.
The answer for mutations accumulating inside cells is about 156 years.
That mutations accumulate with age and can cause cell death is not new. What was missing, as the authors put it, is that their quantitative contribution to limiting human lifespan remains unclear. Previously the claim was directional; this attaches a figure to it.
Nobody lived that long. Nobody in this paper is a real person. What follows is arithmetic about biology, and it is worth reading precisely because it puts a number on something usually left vague.
What the model actually does
The team built an incremental modeling framework that progressively incorporates factors contributing to aging into a model of how populations die off over time.
That structure lets them switch causes on and off. The version reported here estimates lifespan limits if all aging hallmarks were eliminated except somatic mutations.
Somatic mutations are the errors that pile up in the DNA of ordinary body cells across a life. They are not inherited and not passed on. They simply accumulate, and some of them kill the cell that carries them.
The starting point is a theoretical non-aging baseline of 1759 years, which is roughly how long you would last on accidents alone if your body never degraded. Nothing lives that long. It is the yardstick against which the damage gets measured.
Against that yardstick, the model has somatic mutations reducing median lifespan from a theoretical non-aging baseline of 1759 years to 156 years.
The organs that cannot replace themselves
The more interesting result is where the damage bites.
The analysis reveals fundamental asymmetry across organs. Tissues that keep dividing shrug the problem off. Proliferating tissues like liver maintain functionality for thousands of years through cellular replacement, effectively neutralising mutation-driven decline, because a cell carrying a bad copy gets replaced by one that does not.
The cells you keep for life behave completely differently. Post-mitotic cells such as neurons and cardiomyocytes act as critical longevity bottlenecks. A neuron damaged at forty is still the neuron you have at eighty.
So the ceiling is not set by the body as a whole. It is set by the brain and the heart, and specifically by the fact that they do not get to start again.
Put all the organs together and the model predicts median lifespans of 146-194 years, approximately twice current human longevity.
The result the authors are careful about
There is an obvious way to misread this, which is as a promise. The paper closes it off.
The drop from 1,759 years to around 156 is what the authors call this substantial yet incomplete reduction, and the conclusion drawn from it is that somatic mutations significantly drive aging but cannot alone account for observed mortality, implying comparable contributions from other hallmarks.
Read that carefully and it is a statement about how much is left over. People do not currently live to 156. The gap between the model’s mutation-only ceiling and actual human lifespan is the space occupied by everything else that goes wrong with a body, and the authors take its size as evidence that those other processes matter roughly as much.
What a model is and is not
This is computation, not observation. Every number depends on the assumptions built into the framework, and the further the model runs from the data it was fitted to, the more the answer reflects those choices.
A figure like 1,759 years has no empirical referent at all. It exists to make the subtraction meaningful.
The framework also treats aging hallmarks as separable, switching one on while others are off. Biology is not obviously that tidy, and if the processes interact then the arithmetic of removing one is more complicated than the model allows.
Nothing here is a therapy, a target, or a timeline.
Why put a number on it at all
As we age, our minds and bodies change, and people in the U.S. are living longer than they used to, mostly because fewer of them die young.
Work like this is aimed at a different question: not how many people reach old age, but what sets the wall at the end of it. Assigning a share of that wall to a specific, measurable process is more useful than another round of arguing about whether aging is solvable in principle.
The honest headline is the one the authors chose. Mutations matter a great deal, and they are not the whole of it.
People also ask
Is this saying people could live to 156?
No. It is saying that if every other driver of aging were somehow eliminated, mutations accumulating in cells would still cap median lifespan around there. Nobody has eliminated any driver of aging, let alone all but one. The number describes a model's ceiling, not a forecast.
What are somatic mutations?
Errors that accumulate in the DNA of ordinary body cells over a lifetime, as opposed to the ones you inherit. Every cell division and every unrepaired bit of damage adds to the tally. They are not passed to children, and they build up whether or not anything else goes wrong.
Why are neurons and heart cells the bottleneck?
Because you largely keep the ones you are born with. The model calls them post-mitotic, meaning they no longer divide, so a damaged one is not replaced. Tissues that do divide can dilute the problem: the liver maintained functionality for thousands of years in this framework, because damaged cells get swapped out.
Where does 1,759 years come from?
It is the model's theoretical non-aging baseline, the median survival you would get from accident and misfortune alone if bodies never deteriorated. It is a reference point for measuring how much damage each aging process does, not a claim that anything could live that long.
What does the study conclude about other causes of aging?
That mutations are a major driver but not the whole story. Its own reading is that the reduction is substantial yet incomplete, which implies comparable contributions from other hallmarks. In other words, fixing DNA damage alone would not get you to 156, because everything else is still happening.