Scientists believe life expectancy gains will continue to slow as more people become exposed to the downsides of ageing – and their research comes as a separate study shows baby boomers are living longer, but are in poorer health than previous generations.
The rate at which human life expectancy has been rising could be slowing down, new research has suggested - with experts calling for more focus on the number of years people spend in good health.
The rate has slowed considerably in the last three decades after life expectancy nearly doubled over the course of the last 100 years, the study found.
The 19th and 20th centuries saw dramatic increases in how long people could expect to live, mostly due to factors such as healthier diets and advances in medicine.
Now, there may be more immediate potential in improving the quality of life at older ages instead of extending life, the scientists said.
The study suggested it would be optimistic to expect 15% of females and 5% of males to live to 100 years old in most countries this century.
It also indicated that if the processes of biological ageing cannot be slowed, radical human life extension is unlikely during this century.
Researchers said, despite the breakthroughs in medicine and public health, life expectancy for those in the world's longest-living populations has only increased by an average of six and a half years since 1990.
The findings, reported in Nature Ageing, support the idea that life expectancy gains will continue to slow as more people become exposed to the downsides of ageing.
Lead author S Jay Olshansky, of the University Of Illinois Chicago, said: "Most people alive today at older ages are living on time that was manufactured by medicine.
"We should now shift our focus to efforts that slow ageing and extend healthspan."
It comes as results from a separate study on Monday showed baby boomers are living longer - but are in poorer health than previous generations.
Researchers said people aged in their 50s and 60s are more likely to experience serious health problems than people at the same stage who were born during or before the Second World War.
The study, published in the Journals Of Gerontology and compiled by researchers at the University College London and the University of Oxford, found adults born more recently were increasingly likely to have cancer, lung disease, heart problems, diabetes, and high cholesterol as they enter their 50s and 60s.
