They put it down to advanced healthcare systems, lower average-body-
mass indexes (BMIs) and, in South Korea, cabbage, lots of cabbage.

Women are, generally, living longer than men, particularly in South Korea, which is set to become the first nation with an average life expectancy above 90.

An article published on the World Economic Forum website, based on research first published in the Lancet journal, said women born in South Korea in 2030 are projected to be the first in the world with an average life expectancy of above 90.

It noted that France, Japan, Australia, Canada, Chile and the UK were not far behind – all were likely to see women’s average life expectancy at birth pass 85 by 2030.

The research was conducted by the Imperial College London and the World Health Organization, which looked at future life expectancy in 35 industrialised countries.

The researchers predicted that life spans would continue to increase significantly in most of the countries studied.

The US, however, bucked the trend somewhat – here life expectancy will rise more slowly, researchers say. This is due to factors like obesity, unequal access to healthcare and homicide rates.

But what are some of the secrets to the longevity of South Korean women?

One factor to be taken into account is how tall people are. The US, the WEF article noted, is the first wealthy country to experience stagnation or even a possible decline in average adult height – a factor that correlates closely with health and longevity.

“The study, which uses 21 different models to forecast life expectancy, gives South Korean women born in 2030 a 57% chance of exceeding the age of 90, and a 97% probability they will live to be over 86.”

It said South Koreans’ expected longevity is based on the assumption that they will have lower average-body-mass indexes (BMIs) and blood pressure than citizens of other comparable countries.

Kimchi, a hugely popular dish in South Korea, with widely heralded health benefits.

Then there is diet, and particularly its famous dish, Kimchi. Based on fermented vegetables – usually cabbage – it is high in probiotics and vitamins A and B.

Other factors that come into play are nutritional education, advances in economic and social status, lower road-traffic accident rates and high-quality healthcare systems, which improve prevention and survival rates from serious diseases and reduce infant mortality.

Nature.com said some of the reasons for the nation’s dramatic improvements since the 1980s were improved economic status and advances in child nutrition.

We are usually told the key to living to a ripe old age is a healthy diet and plenty of exercise.

But for those wanting to reach 100, it seems a sheer determination to carry on could also keep us alive.

Having a positive outlook, stubbornness and continuing to keep busy could be key to a long life, a study suggests.

Love of one’s family, a strong work ethic and religious faith were also factors.

Researchers studied 29 people aged between 91 and 101, who were unsurprisingly found to have worse physical health than their family members aged 51 to 75.

But when it came to mental health, the oldest inhabitants of nine villages in Cilento, southern Italy, were found to be in better shape than younger relatives, suggesting that advancing years lend a greater sense of well-being.

The study by the University of Rome and University of California San Diego also found high self-confidence and decision-making skills among the very old group.

Lead author Anna Scelzo said: “The group’s love of their land is a common theme and gives them a purpose in life. Most of them are still working in their homes and on the land. They think, ‘This is my life and I’m not going to give it up’. We also found that this group tended to be domineering, stubborn and needed a sense of control, which can be a desirable trait as they are true to their convictions and care less about what others think.

“This tendency to control the environment suggests notable grit that is balanced by a need to adapt to changing circumstances.”

The researchers assessed mental and physical health, and also let the participants tell their life stories. Topics included traumatic events, migration and their beliefs.

Among those interviewed was a long-living man who had lost his wife of 70 years and had been left feeling empty after her loss a month before. He said: “Thanks to my sons, I am now recovering and feeling much better. I have four children, ten grandchildren and nine great-grandchildren. I have fought all my life and I am always ready for changes.

“I think changes bring life and give chances to grow.”

One nonagenarian said: “I am always thinking for the best. There is always a solution in life. This is what my father taught me – always face difficulties and hope for the best.”

Another quoted in the study, published in International Psychogeriatrics, said: “I am always active. I do not know what stress is. Life is what it is and must be faced always.”

One participant said: “I feel younger now than when I was young.”

Dr Dilip Jeste, professor of psychiatry at UCSD, said: “There have been a number of studies on very old adults, but they have mostly focused on genetics rather than their mental health or personalities.

“The main themes that emerged from our study, and appear to be the unique features associated with better mental health of this rural population, were positivity, work ethic, stubbornness and a strong bond with family, religion and land.”

Jeste added: “This paradox of ageing supports the notion that well-being and wisdom increase with ageing even though physical health is failing.

“Studying the strategies of exceptionally long-lived and lived-well individuals, who not just survive but also thrive and flourish, enhances our understanding of health and functional capacities in all age groups.”

A previous study looked at the diet and lifestyle of residents in Acciaroli, south-west Italy, where one in 10 locals lives past the age of 100. It found many elderly locals continued to enjoy an active sex life and a healthy Mediterranean diet featuring olive oil, fresh fruit, home-grown vegetables and fish.

 Consuming high-salt diet may be harmful as it may increase the risk of dementia later in life, warns a recent study.

Researchers from Weill Cornell Medicine in New York explained that high-salt diet reduces resting blood flow to the brain and causes dementia in mice.

The study is the first to unveil a gut-brain connection, linking high dietary salt intake to neurovascular and cognitive impairment.

The findings illuminate a potential future target for countering harmful effects to the brain caused by excess salt consumption.

The researchers explained that mice fed a high-salt diet developed dementia even when blood pressure did not rise.

Researchers Senior author Dr. Costantino Iadecola, director of the Feil Family Brain and Mind Research Institute (BMRI) and the Anne Parrish Titzell Professor of Neurology at Weill Cornell Medicine.

“This was surprising since, in humans, the deleterious effects of salt on cognition were attributed to hypertension”, they added.

The mice were given food containing four percent or eight percent salt, representing an 8 to 16 fold increase in salt compared to a normal mouse diet.

The higher level was comparable to the high end of human salt consumption.

After eight weeks, the team examined the mice using magnetic resonance imaging.

The results revealed that the mice showed marked reductions in resting cerebral blood flow in two areas of the brain involved in learning and memory: 28 percent decrease in the cortex and 25 percent in the hippocampus.

The scientists discovered that an impaired ability of cells lining blood vessels, called endothelial cells, reduced the production of nitric oxide, a gas normally produced by the endothelial cells to relax blood vessels and increase blood flow.

Rodents that only ate the high-salt diet developed dementia, performing significantly worse on an object recognition test.

The research appears in Nature Neuroscience journal.