The researchers suggest their predictions of increasing life expectancy reflect the success of public health and healthcare. However, they also urge nations to put in place policies to support the growing older population.
The study - led by Imperial College London in the United Kingdom and conducted in collaboration World Health Organization (WHO) - is published in The Lancet.
The team used 21 models based on weather forecasting techniques to analyze long-term patterns of mortality and longevity in 35 industrialized countries and combined the results depending on how well the models performed.
The results suggest it is likely that life expectancy of babies born in 2030 in:
- South Korea will be 90.8 years, France 88.6 years, and Japan 88.4 years if they are female
- South Korea will be 84.1 years, Australia 84.0 years, and Switzerland 84.0 years if they are male
Lead author Majid Ezzati, a professor in the School of Public Health at Imperial College, says: "Many people used to believe that 90 years is the upper limit for life expectancy, but this research suggests we will break the 90-year-barrier."
"I don't believe we're anywhere near the upper limit of life expectancy - if there even is one," he adds.
Prof. Ezzati and colleagues advise that rising life expectancies will present nations will major challenges in providing health and social services and pensions. They will need to adapt their policies and increase investment to ensure they support healthy aging. Retirement age may also have to change, they note.
U.S. falling behind
While the researchers predict that life expectancy is likely to rise across all 35 countries, the size of increase varies.
For example, the United States is likely to see only small improvements: rising by 2.1 years (from 81.2 in 2010 to 83.3 in 2030) for women and 3.0 years (76.5 to 79.5) for men.
U.S. life expectancy is already lower than most other high-income nations, and these predictions suggest it is expected to fall further behind; in 2030 the U.S. will have similar life expectancies as middle-income countries like Croatia and Mexico.
Ranking the 35 countries by predicted increase in life expectancy from 2010-2030 for women and men places the U.S. in the bottom four in each case. The other countries languishing at the bottom are: Macedonia, Bulgaria, and Japan (increases predicted to be 1.4, 1.5, and 1.8 years respectively for women), and Macedonia, Greece, and Sweden (2.4, 2.7, 3.0, respectively for men).
In contrast, in countries where life expectancy is likely to increase the most, the increases are considerably larger. A baby girl born in 2030 can expect to live 6.6 years longer in South Korea, 4.7 years longer in Slovenia, and 4.4 years longer in Portugal than a baby girl born in 2010. For baby boys the highest predicted increases in life expectancy are: 7.5 years in Hungary, 7.0 years in South Korea, and 6.4 years in Slovenia.
The researchers suggest the large increases in South Korea's life expectancy figures could be a result of continued improvement in the country's economic status, which has improved children's nutrition and given more people of all ages and across the population better access to healthcare and medical technology.
Conversely, they suggest large inequalities and lack of universal health care are among the reasons the U.S. is falling behind.
They note the U.S. also has the highest homicide rate, the highest rates for obesity and overweight, and the highest rates of mother and child deaths of all high-income nations.
The researchers calculated a country's life expectancy at birth by assessing the age at which people die across the whole population. For example, countries with high rates of death in childhood will tend to have lower average life expectancies, as would countries where many young people die from injuries and violence.
As well as calculating life expectancy at birth, the team also predicted how many more years people who reached the age of 65 at 2030 were likely to live.
They found that in 11 of the 25 countries, senior women were likely to live an addition 24 years, and in 22 of the countries, senior men were likely to live an additional 20 years.
More specifically, the results show that:
- The five countries where men who are 65 years old in 2030 are likely to live the longest are: Canada (22.6 additional life years), New Zealand (22.5), Australia (22.2), South Korea (22.0), and Ireland (21.7)
- The five countries with the highest life expectancy for 65-year-old women in 2030 are likely to be: South Korea (27.5 additional life years), France (26.1), Japan (25.9), Spain (24.8), and Switzerland (24.6)
The researchers say this shows that across most of the developed world, older populations are likely to continue growing.
"Our predictions of increasing lifespans highlight our public health and healthcare successes. However, it is important that policies to support the growing older population are in place. In particular, we will need to both strengthen our health and social care systems and to establish alternative models of care such as technology-assisted home care."
Prof. Majid Ezzati