Scientists researching human lifespan have concluded that it has no detectable limit, and that with advances in technology and medicine it could continue to climb for the foreseeable future.
“We just don’t know what the age limit might be,” said study co-author Siegfried Hekimi, a biologist from McGill University.
“In fact, by extending trend lines, we can show that maximum and average lifespans could continue to increase far into the foreseeable future.”
The study, which is published today in the journal Nature, analysed the lifespan of the longest-surviving people from Japan, France, the UK and the US every year from 1968 to the present day.
The scientists found that there was no evidence that a limit on lifespan exists, and concluded that if it does, we certainly have not yet reached it or even identified what it could be.
The research flies in the face of previous studies that concluded that not only was there a limit of 115 years, but that we were beginning to reach it. However Hekemi and his colleague Bryan G Hughes do not believe this is the case, and are unable to even hazard a guess as to what such a limit could be.
“It’s hard to guess,” Hekimi said. “Three hundred years ago, many people lived only short lives.
“If we would have told them that one day most humans might live up to 100, they would have said we were crazy.”
Average lifespans have jumped significantly over the past century. In 1920, Canadians had an average expectancy of 60 years, but by 1980 it had climbed to 76 years. Now it is 82 years, and is likely to climb further.
These jumps have been down to the revolution in medical science over the last hundred years, however advances in medical technologies could cause a significant further jump in our lifetimes.
In particular, work by organisations such as the SENS Research Foundation, led by noted gerontologist Aubrey de Grey, is focused on treating ageing as something that can be cured, and has seen growing support from the mainstream scientific community.
However, if such medical treatments do become available, they may only be available to those that can afford them, particularly in countries that do not have a single-payer healthcare system, such as the US. In these instances, there are fears that such treatments could divide humanity, with the rich gaining far longer lifespans than the poor.