When Besse Cooper died in 2012 at age 116, she had the distinction of being the oldest living person in the world. The Georgia native had lived on a farm for most of her life and enjoyed good health. She attributed her longevity to lifestyle choices, which included avoiding junk food.
Even as human life expectancy has risen steadily in the past 150 years, a new study published in the journal Nature reports that humans have reached the upper limit of longevity. The research suggests that in spite of improvements in life expectancy, the human life is limited to around 115 years. Even with advancements in health care, the body simply wears out and can’t fix itself.
“Our results strongly suggest that the maximum lifespan of humans is fixed and subject to natural constraints,” the researchers wrote.
Life expectancy is a population-based estimate of the duration of life for individuals, and maximum lifespan refers to the age reached by the longest-living members of a species.
Data tell the story
The team of researchers, led by Jan Vijg, a professor of genetics and an expert on aging at the Albert Einstein College of Medicine, studied data on survival and mortality around the world since 1900. They noted that “improvements in survival with age tend to decline after age 100,” and since the 1990s there hasn’t been an uptick in the age of the oldest humans recorded.
There will be outliers, like Jeanne Calment, who died in 1997 at 122, but Vijg calculates that the probability of a person exceeding 125 in any given year is less than 1 in 10,000.
The team’s findings are not new. Researcher Jay Olshansky, a professor of public health at the University of Illinois at Chicago, has posed the same argument for 25 years.
In a paper published in Nature earlier this year, Olshansky wrote: “Humanity is working hard to manufacture more survival time, with some degree of success, but we should acknowledge that a genetically determined fixed-life history strategy for our species stands in the way of radical life extension.”
Not everyone agrees with the idea that humans have a shelf life. A growing number of supercentenarians — people who live to be 110 and older — along with studies on animals whose lifespans can be extended through genetic or dietary changes, leads many researchers to believe there is no upper limit on human lifespan.
At the Salk Institute of Biological Studies in La Jolla, Calif., researchers believe they have discovered the main cause of aging and potentially, a way to counter or slow the process. Scientists found that the genetic mutations responsible for Werner syndrome, a disorder that leads to premature aging and death, destroyed bundles of DNA known as heterochromatin. The discovery “could lead to ways of countering age-related physiological declines by preventing or reversing damage to heterochromatin,” the scientists said.
Though more research is necessary, Salk researchers are hopeful they’ll figure out how to extend life and prevent age-related diseases such as Alzheimer’s.
Healthy life span
If your goal is to be healthy throughout your life – even if you don’t reach supercentenarian status – there are abundant resources to help you.
The National Institute on Aging has expert information on healthy aging and longevity, plus a wide array of resources, including books, reports and latest news.
To read the report in Nature, click here.
You can learn more about the Salk Institute’s study in the journal Science.
Talk to your health care provider about aging healthy. Don’t have a provider? You can find a Providence provider here.