The increase of life expectancy in humans has slowed, with a time when the average age is 100 slipping further into the future.
A new study compared the life expectancies of people born throughout 20th century and showed life expectancy for those born between 1939 and 2000 was rising more slowly than in the past.
Study lead author José Andrade, from the Max Planck Institute for Demographic Research, in Germany, said life expectancy rose at an almost dizzying rate at the beginning of the 20th century.
Mr Andrade said people born in 1900 lived to an average age of 62, whereas those born in 1938 lived to around 80.
“If today’s generations were to follow the same trend as the one observed during the first half of the 20th century, someone born in 1980, for example, could expect to live to 100,” he said.
“We investigated whether the pace of life expectancy gains is slowing down for current alive cohorts.”
Mr Andrade said the team anaylsed data from the Human Mortality Database (HMD) and used six different mortality forecasting methods.
“To ensure robust results, we did not just use one method, but several: some well-established ones, including the United Nations World Population Prospects, and others representing the cutting edge of mortality forecasting.”
Mr Andrade said all forecasting methods showed that life expectancy for those born between 1939 and 2000 is rising more slowly than in the past.
“Depending on the method used, the rate is slowing by between 37 and 52 percent,” he said.
“We forecast that those born in 1980 will not live to be 100 on average, and none of the cohorts in our study will reach this milestone.”
Mr Andrade said the decline was largely due to the fact that past surges in longevity were driven by remarkable improvements in survival at very young ages.
He said from 1900 to 1938, life expectancy rose by about five and a half months with each new generation.
“For those born between 1939 and 2000, the increase slowed to roughly two and a half to three and a half months per generation, depending on the forecasting method.”
Mr Andrade said mortality forecasts could never be certain as the future may unfold in unexpected ways.
“Events such as pandemics, new medical treatments or societal changes can significantly affect actual life expectancy.”
Read the full study: Cohort mortality forecasts indicate signs of deceleration in life expectancy gains.
