The demography of human lifespan is a controversial topic in the science community. There have been many theories surrounding the biological limits to human longevity. The theories that are based upon evolution greatly depend on data regarding death rates at extreme ages. Scientists have continued to debate these facts.
In an Italian study, researchers found that when people reached the age of 105, they weren’t as likely to die instantly. Scientists believe, according to a report published in the journal Science, that people may actually be evolving to have longer life expectancies.
The research team had the following to say about their study, which they claim is “free from artifacts of aggravation” that restricted previous studies.
“On the basis of high-quality data from Italians aged 105 and older, Barbi et al. show that mortality is constant at extreme ages but at levels that decline somewhat across cohorts. Human death rates increase exponentially up to about age 80, then decelerate, and plateau after age 105.”
The research team, led by Elisabetta Barbi of the Sapienza University of Rome, wrote that the mortality rate beyond age 105 declines, which suggests that human longevity of life is increasing continuously over time. Barbi believes that, if there is a limit on how long a human can live, it has not yet been reached.
According to a recent NBC News report, it can be complicated to study those of “extreme age.” In fact, “even in countries with reliable vital registration, age exaggeration is common among the oldest old.” It wasn’t until just recently that birth date verification has been possible for individuals over 100 years of age.
Barbi’s team of researchers collected verified data from Italy. According to their report, “the project includes all individuals 105 and older in the period from 1 January 2009 to 31 December 2015.”
The team obtained birth details on 3,836 Italians who were older than 105. What they found, when plotting the mortality of these individuals, was a pattern. When people reached the age of 105, there was a distinct decrease in the rate of death. The mortality rates were lower as they got older.
“By using clean data from a single nation and straightforward estimation methods, we have shown that death rates, which increase exponentially up to about age 80, do decelerate thereafter and reach or closely approach a plateau after age 105.”
There have been other studies that have also come to a similar conclusion. They have found that “super-centenarians are exceptionally healthy” considering how old they are. It seems as if, the oldest of the old do not tend to “live their last years being sick and frail.”
“The longest validated lifespan is for Frenchwoman Jeanne Calment, who died in 1997 when she was 122 years and 167 days old.”
Unfortunately, in the United States, the trend is moving the wrong way. Life expectancy in the U.S. is falling. According to recent reports from the Centers for Disease Control and Prevention, life expectancy within a nation falls with citizens begin to die at younger ages. Due to the opioid epidemic and overdose rates, the life expectancy in the U.S. has continued on a downward trend for two consecutive years.
A report from the National Center for Health Statistics “shows the decline in life expectancy occurred despite an overall decline in U.S. mortality.”