For most of the 20th century, a quiet assumption ran through American life: each generation would outlive the one before it. Better medicine, better food, better lives. It held true, decade after decade, until it stopped.
A new analysis published in the Proceedings of the National Academy of Sciences finds that Americans are dying younger—no longer an anomaly, but a trend. People born after 1970 are already dying at higher rates from heart disease, cancer, and external causes than earlier generations did at the same ages. The researchers behind the study warn that the worst may still be ahead.
Between 2010 and 2019, U.S. life expectancy improved by only 0.26 years, compared to an average gain of 1.78 years per decade over the previous five decades. Among 22 peer nations, the gap in life expectancy at birth between the U.S. and the top-performing country grew from 2.6 years to 4.7 years between 1983 and 2009. Stagnation barely covers what those numbers describe.
The Generational Turning Point: Born in the 1950s, Dying Faster
Americans born between 1950 and 1959 marked the generational turning point. Across every major cause of death examined—cardiovascular disease, cancer, external causes like overdoses and suicides—this group showed worse death rates compared to people born just before them, when both groups are measured at the same ages.
People born in the 1940s tended to see steadily improving survival at each stage of life. For those born in the 1950s, that improvement slowed or reversed. Several explanations have been proposed: widespread cigarette smoking at young ages, the long-term damage caused by the HIV/AIDS epidemic and early waves of opioid addiction, and the toll of a generation shaped partly by social instability. Sharply worse lung cancer death rates below age 60 for this cohort are consistent with early smoking patterns, the researchers note.
On top of these generational patterns, the researchers identified a separate, nationwide deterioration that began around 2010 and affected nearly every adult alive at the time, regardless of when they were born. Someone in their 30s in 2012 experienced worsening trends. So did someone in their 70s. This society-wide setback was driven primarily by cardiovascular disease, which had been declining for decades before its progress stalled.
Why Post-1970 Cohorts Are the Most Alarming
Among all the findings, the most alarming concern is that Americans born after 1970. At the ages these people have already reached—roughly 30 to 49 depending on the cause of death examined—they are already dying at higher rates from heart disease, cancer, and external causes than people born just before them were dying at those same ages.
Colon cancer, strongly tied to obesity and diet, is a particular concern, with death rates rising at younger ages beginning with cohorts born around 1955 and worsening from there. Drug overdose deaths, which increased sharply beginning in the late 1990s, hit post-1970 cohorts especially hard. Among women, suicide death rates began worsening around 2000 and, by 2010, affected nearly every age group. Homicide and traffic accident death rates also worsened in the 2010s.
Because people born after 1970 are still in the middle stages of their lives, the full impact has not yet appeared in overall life expectancy figures. These generations have decades of aging ahead of them, and if their elevated death rates at young and middle ages are any indication, their outcomes in old age could drag down American life expectancy in ways not yet fully felt. Researchers describe this trajectory as pointing toward a possible “unprecedented longer-run stagnation, or even sustained decline, in U.S. life expectancy.”
The Upstream Factors: Obesity, Inequality, Stress
No single cause explains any of this, and the paper does not test which factors mattered most. Cigarette smoking laid the groundwork for cancer and heart disease deaths in older generations. Obesity is shaping the health of younger ones. Researchers point to rising economic and social inequality, the opioid epidemic, and stress as likely forces, noting that these upstream factors may affect multiple causes of death simultaneously: smoking drives both cancer and heart disease, stress is linked to cardiovascular risk and substance abuse, and cancer treatments can in turn worsen heart health.
Researchers do not test specific policy solutions in this paper, but they point to rising economic and social inequality as a driver of American mortality trends, and note that “policies aimed at reducing social inequalities and improving resources for socioeconomically disadvantaged groups can be powerful levers in improving national trends.”
Worth noting as well: modest improvements in death rates in 2018 and 2019 were erased by sharply rising mortality between 2019 and 2022, with only partial recovery by 2023.
The Long-Running Warning Sign
For the generations coming up behind the baby boomers, what this analysis describes is less a temporary stumble in an otherwise upward march than a long-running warning sign that has been building for decades. Successive cohorts are arriving at middle age already bearing higher mortality burdens than their predecessors, and they have decades left to age into a system that still struggles to explain why.
The assumption that each generation would outlive the one before it held true for most of the 20th century. It doesn’t hold anymore.
Source: Study Finds