Researchers identified slower gains in longevity, especially in young ages
-
Life expectancy increases in many high-income countries are decelerating: the rapid gains seen earlier in the 20th century are tapering off.
-
A big part of this slowdown comes from diminishing improvements in child and infant mortality once a major driver of longer lives.
-
According to the forecasts, no cohort born after 1939 is projected to reach an average lifespan of 100 years.
For decades, many of us have assumed that each successive generation will live longer than the last and maybe even average 100 years someday.
But recent research suggests we might be approaching the limits of how much life expectancy can keep increasing, at least under current conditions.
A new study, drawing on data from multiple high-income countries, shows that improvements in longevity are not just slowing; they may be slowing permanently, especially for people born in more recent decades. If you were born after 1939, the odds are you wont live to see your 100th year on average.
The unprecedented increase in life expectancy we achieved in the first half of the 20th century appears to be a phenomenon we are unlikely to achieve again in the foreseeable future, researcher Pifarr i Arolas said in a news release.
In the absence of any major breakthroughs that significantly extend human life, life expectancy would still not match the rapid increases seen in the early 20th century even if adult survival improved twice as fast as we predict.
The study
The research looked at cohort life expectancy among individuals born between 1939 and 2000 in 23 high-income, low-mortality countries.
Cohort life expectancy accounts for the actual mortality experience of a generation across its life span. Period life expectancy, on the other hand, estimates how long someone would live if current death rates at each age stayed the same.
The researchers used six different forecasting methods to predict future mortality and importantly, they performed robustness checks to make sure their findings were not due to odd data quirks or biases. They also decomposed age-specific trends to see which age groups drove the slowdown.
The results
Heres a look at how the results broke down:
-
Slower increases in life expectancy. Historically, cohorts born early in the 20th century saw life expectancy rise by about 0.46 years per generation (thats about 56 months). But for those born later (19392000), that gain has dropped by 37% to 52%, depending on the forecast method.
-
Young-age mortality improvements taper off. Over half of the slowdown in gains comes from weak or diminishing gains in mortality under age 5; more than two-thirds come from under age 20. In other words, early childhood mortality was once a major lever for increasing life expectancy and that lever has already been heavily pulled.
-
Universal 100-year lifespans are unlikely for newer generations. Based on these forecasts, the researchers conclude that none of the cohorts born after 1939 are expected to reach an average life expectancy of 100. Even people born around 1980 are predicted to fall short.
-
Why this matters. These findings suggest that unless something major changes new medical breakthroughs, better public health in older ages, etc. we shouldnt expect life expectancy to keep shooting up as fast as it once did. For people planning for retirement, health systems preparing for ageing populations, or governments budgeting for pensions, this shift could have real implications.
Posted: 2025-09-18 18:03:33