Researchers from Imperial College London and the World Health Organisation analysed the lifespan of citizens from 35 industrialised countries, with a mix of high income nations and emerging economies, and found that the average global life expectancy at birth was 71.4 years at 2015, and will continue to increase by 2030.

South Korean women are in the lead, with an average life expectancy predicted to be 90.8 years, while South Korean men will be at 84.1 years.

“The biggest result is that ... at least one group is going to break the 90-year barrier,” said Majid Ezzati, professor of global environmental health at Imperial College London who led the study.

“We should be planning for more life”

This is significant as it had long been believed that the average life expectancy would never exceed 90.

“This shows that even if there is a limit to longevity, we are nowhere near it,” he said. "We should be planning for more life."

Earlier increases in life expectancy were a result of declining infection-related mortality for children and adults, however, “more recent gains have been largely due to postponement of death from chronic diseases”, according to the authors of the study.

Following South Korea, female life expectancies in France and Switzerland will be 88.6 and 84 years respectively. Women have long held a longer life expectancy than men on average. This is attributed to unhealthier lifestyles among the latter.

“Men traditionally had unhealthier lifestyles, and so shorter life expectancies,” explained Ezzati. “They smoked and drank more, and had more road traffic accidents and homicides, however, as lifestyles become more similar between men and women, so does their longevity.”

Western diets affect Asia’s younger generation

At the same time, countries long noted for their longevity like Japan, are predicted to experience much smaller increases in life expectancy. The traditionally healthy diets and active lifestyles of the Japanese have ensured that Japanese women currently have the world’s highest life expectancy.

Nevertheless, “the Japanese story has started to come to an end,” according to Ezzati. While Japanese people “still have low obesity and low blood pressure”, Western influences such as diet, “are catching up”. This phenomenon is not unique to Japan.

“… in many parts of Asia, young people are eating Western diets. ... The (previously) healthy diet may not be sustained as young people reach older ages,” said Sarah Harper, professor of gerontology at the University of Oxford.

“South Korea has caught up with Japan as its standard of living has increased,” she added. Male life expectancy in Japan is also set to drop in rank from the fourth highest to 11th out of the countries studied.

Access to healthcare a major factor

The lowest life expectancies occurred for women in Macedonia and men in Serbia, where they have a relatively high mortality risk in their 40s or 50s. Many reasons were abound, including greater obesity rates and their associated health risks, violence and accidents, as well as inequality in access to healthcare.

The US is projected to have the lowest life expectancy at birth among high-income countries - 83.3 years for women and 79.5 years for men – akin to those in Mexico and Croatia.

“The US spends more of its budget on health care than any other country in the world. Some say this is due to the huge amount of inequality,” said Harper.

The findings have great implications for policymakers to improve the welfare of citizens and prepare for changing demographics in their countries’ populations. According to Ezzati, South Korea owes its success to its emphasis on good healthcare access, childhood nutrition, education, technology and lifestyle, which lead to low levels of smoking and low blood pressure.

“Places that perform well do so by investing in their health system and making sure it reaches everyone,” concluded Ezzati. MIMS

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