People like Jeanne Calment of France – who famously lived to be 122 years old, setting a world record in the process – have led scientists to wonder how long a person could live, and a report published last October in the journal Nature concluded that the upper limit of human longevity is peaking at about 115 years.
However, new research by biologists at McGill University in Canada disputes that finding.
To determine whether there is a limit to human longevity, and what it may be, the team analyzed the life spans of the longest-living individuals from the United States, France, Japan and the United Kingdom for each year since 1968.
The analysis did not detect a limit. If such a maximum exists, it has yet to be identified or reached, according to Siegfried Hekimi, co-author of the new study, which was published Wednesday in Nature.
“We just don’t know what the age limit might be. In fact, by extending trend lines, we can show that maximum and average life spans, could continue to increase far into the foreseeable future,” Hekimi said.
The team points to Canada as an example of this trend, pointing out that the average baby born in 1920 could expect to live 60 years. That figure jumped to 76 years in 1980, while a Canadian born today can expect to live to be 82 years old. The upper limit of age seems to follow this trend as well.
Improvements in medical interventions, technology and living conditions could each increase a potential maximum life span, which makes it difficult to predict what future human life spans 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.”