Despite advances in medicine, gains in life expectancy are slowing

We saw a dramatic increase in life expectancy during the 19th and 20th centuries, thanks to healthier diets, advances in medicine, and many other improvements in the quality of life.

But after nearly doubling during the 20th century, the rate of increase has slowed significantly over the past three decades, according to a new study led by the University of Illinois at Chicago.

Despite frequent advances in medicine and public health, life expectancy at birth in the world’s oldest populations has increased by an average of only six and a half years since 1990, according to the analysis. This rate of improvement is far below some scientists’ expectations that life expectancy would increase at an accelerating rate this century and that most people born today would live beyond 100 years.

THE Natural aging The paper titled “Implausibility of the Radical Extension of Life in Humans in the 21st Century” offers new evidence that humans are approaching a biological limit to life.

The greatest improvements in longevity have already occurred because of successful efforts to combat the disease, said lead author S. Jay Olshansky of the UIC School of Public Health. The harmful effects of aging therefore remain the main obstacle to further expansion.

“Most of today’s older adults are living according to medically manufactured time,” said Olshansky, a professor of epidemiology and biostatistics. “But these medical dressings produce fewer years of life, even though they are occurring at an accelerated rate, implying that the period of rapid increases in life expectancy is now over.”

It also means that further extending life expectancy by reducing disease could be harmful, if those extra years are not healthy years, Olshansky added. “We should now focus on efforts to slow aging and extend life expectancy,” he said. Healthspan is a relatively new metric that measures the number of years a person has been healthy, not just alive.

The analysis, conducted with researchers from the University of Hawaii, Harvard and UCLA, is the latest chapter in a three-decade debate over the potential limits of human longevity.

In 1990, Olshansky published an article in Science which claimed that human life expectancy was approaching a ceiling of around 85 years and that the most significant progress had already been made. Others predicted that advances in medicine and public health would accelerate 20th-century trends into the 21st century.

Thirty-four years later, the evidence reported in the 2024 Natural aging This study supports the idea that gains in life expectancy will continue to slow as more people become exposed to the adverse and unchanging effects of aging. The study looked at data from the eight countries with the longest life expectancies, Hong Kong and the United States, one of the few countries to experience a decline in life expectancy over the period studied.

“Our results overturn the conventional wisdom that our species’ natural longevity lies somewhere on the horizon, a life expectancy beyond where we are today,” Olshansky said.

“Instead, it’s behind us, somewhere between 30 and 60 years. We have now proven that modern medicine produces smaller and smaller improvements in longevity, even though medical advances occur at a dizzying speed.”

Even though more people may reach 100 and older this century, these cases will remain outliers that will not significantly increase average life expectancy, Olshansky said.

This conclusion flies in the face of products and industries, such as insurance and wealth management companies, that increasingly make calculations based on the assumption that most people will live to be 100 .

“This is very bad advice because only a small percentage of the population will live that long in this century,” Olshansky said.

But these results do not exclude that medicine and science can produce other benefits, he said. According to the authors, there may be more immediate potential in improving the quality of life of older people rather than prolonging life. We should invest more in gerosciences, the biology of aging, which could contain the seeds of the next wave of health and life extension.

“It’s a glass ceiling, not a brick wall,” Olshansky said. “There is still much to do: reducing risk factors, working to eliminate disparities, and encouraging people to adopt healthier lifestyles – all of which can help people live longer, healthier lives.” We can break through this glass ceiling on health and longevity through geroscience and efforts to slow the effects of aging.