A recent study published in Nature Aging reveals that the substantial gains in human life expectancy during the 20th century are now slowing down, suggesting that wealthy nations may be nearing a limit on how long people can live—at least for now.
Researchers from the University of Illinois Chicago (UIC) analyzed national vital statistics from 1990 to 2019 across ten high-income countries known for their long-living populations: Australia, France, Italy, Japan, South Korea, Spain, Sweden, Switzerland, Hong Kong, and the United States.
Their findings reveal that since 1990, the average lifespan in these countries has increased by only 6.5 years. This modest rise casts doubt on the expectation that human life expectancy will exceed 100 years for those born today.
Dr. S. Jay Olshansky, the study’s co-author and a professor of epidemiology and biostatistics at UIC, expressed that the improvements in life expectancy are decelerating.
“As long as aging remains unchanged, extending life through disease reduction yields diminishing gains,” he stated. Olshansky pointed out that the decline in improvement was particularly pronounced in the United States.
He introduced the concept of “manufactured time,” suggesting that most people over the age of 60 are surviving due to medical advancements rather than natural longevity. “Humans were not made to live as long as they do now,” Olshansky noted, explaining that the natural life expectancy for humans ranges between 30 to 60 years.
The additional years many enjoy today are largely thanks to medical interventions that act as temporary solutions without altering the fundamental aging process.
Not all experts agree with the study’s conclusions.
Dr. Marc Siegel, a senior medical analyst and clinical professor of medicine at NYU Langone Medical Center, contested the idea that life expectancy gains have plateaued.
“Aging is tied to inflammation,” he explained. “Current treatments and dietary strategies that decrease oxidative stress, inflammation, and insulin resistance contribute to cellular longevity.”
Dr. Nicole Saphier, a medical contributor and practicing physician, acknowledged that while medical advancements have allowed people to live longer, these years are not necessarily healthier.
“Recently, life expectancy seems to be on a downward trend,” she observed. Saphier attributes this decline to factors like the consumption of ultra-processed foods and decreased physical activity. “Many rely on medication to offset chronic diseases, but this approach is expensive and doesn’t offer a great quality of life,” she added.
Olshansky noted the need to prioritize extending the “healthspan”—the period of life spent in good health—over merely increasing the number of years lived.
“We should control what we can by avoiding activities that shorten lifespan, such as unhealthy eating, smoking, and substance abuse,” he advised. He also encouraged people to take advantage of medical care and prescribed medications to improve their chances of living longer and healthier lives.
Dr. Saphier concurred, stressing the importance of preventing chronic diseases through healthier diets, increased physical activity, and nurturing mental health via strong relationships with family, faith, and friends.
“Life expectancy is just a number,” she remarked. “It’s about the quality of years lived, not just the quantity.”
While the study suggests that we may be nearing a natural limit to human life expectancy, the conversation around aging and longevity is far from over.
Advances in medical technology and a better understanding of the aging process could potentially lead to breakthroughs that extend both lifespan and healthspan.
For now, focusing on healthy living and preventive care remains the most practical approach for individuals seeking to make the most of their years.