How long can humans live? The answer has always seemed to be the same: It depends. But now we might have a clearer answer, as researchers at Tilburg University in the Netherlands and Erasmus University Rotterdam recently announced they’ve identified the upper limit for our species.
In a study that has not yet been peer-reviewed, these researchers report that the maximum age for women is 115.7 years, and the maximum age for men is 114.1 years. They also concluded that, over the last 30 years, there has been no significant increase or decrease in maximum lifespan.
To come to these conclusions, they analyzed 30 years’ worth of data on the age at which 75,000 Dutch people died, using a branch of statistics called Extreme Value Theory. This theory, which is normally used to make predictions about extreme (that is, rare) events using information about less extreme events, allowed them to estimate the maximum possible human age based on average human lifespans.
“If [the ages] are far apart, it points at a higher maximum age; if the distances between the life spans become smaller and smaller, it points at a lower maximum age,” Professor Emeritus Laurens de Haan of Erasmus University Rotterdam, a co-author of the paper, tells Inverse.
The data suggest that, even as average lifespans are increasing, we probably still can’t live past a certain age. Why that’s the case, however, is a question that de Haan has yet to answer.
He’s careful to point out that his team’s research doesn’t provide any specific insights into how a person could extend their life because their findings are derived from data on a very specific population — people who have died in the Netherlands since 1986 — that doesn’t include any additional demographic or health-related data.
There will always be outliers, such as Jeanne Calment, the French woman who died at the age of 122 in 1997, or Mbah Gotho, the Indonesian man who claimed to be 146 years old when he died in April. Such cases don’t disprove his team’s findings, says de Haan.
“Extreme Value Theory allows us to estimate this ceiling, but as with all statistical estimates, there is necessarily some uncertainty involved,” he says. “That is, there is a confidence interval that covers, for example, the age of Madame Calment.”
These maximum lifespan values support the main findings of a 2016 study, published in Nature, in which researchers argued that “the maximum lifespan of humans is fixed and subject to natural constraints.” That study concluded that the statistical ceiling for human lifespan was 114.9 years. Contrary to the new Dutch paper’s findings, though, the Nature paper concluded that the maximum age has increased and then decreased.
“As you know, there is no scientific consensus about this,” says de Haan.
The researchers of the Nature paper drew lots of criticism, which led the journal to publish a special series of responses. Critics characterized their analysis as deeply flawed. In one of the editorial responses to that paper, European researchers outlined their issues with the statistics involved. Their message was unequivocal: “We believe these authors’ analyses, and, hence, their conclusions to be flawed,” they wrote.
Though the latest research from de Haan and team ultimately reaches a similar conclusion to the 2016 Nature paper, it seems to stand on much firmer ground.
“I’m delighted to see that the authors of this new paper have used Extreme Value Theory, which is an appropriate analysis that we recommended in our letter,” the University of Edinburgh aging expert Stuart Ritchie, Ph.D., one of the critics of the Nature paper, tells Inverse. “I’m looking forward to reading the new paper when it appears.”