People are living longer and fewer are dying from infectious disease, but this progress in health is no guarantee of living happily and healthily. In fact, international experts warn to brace ourselves for the next pandemic: chronic diseases - and as a result, disabilities.
Two in three deaths worldwide (34.5 million) were from chronic diseases in 2010 - an increase of about eight million between 1990 and 2010, according to the landmark Global Burden of Disease Study 2010 published in The Lancet last month, a collaborative project by nearly 500 scientists from more than 300 institutions in 50 countries.
Comparing 2010 and 1990, eight million people died from cancer, a 38 per cent increase; one in four deaths (12.9 million) was from heart disease or stroke, versus one in five; and diabetes killed twice as many people, or 1.3 million. Conversely, one in four deaths was due to communicable diseases and maternal, neonatal, or nutritional causes - down 34 per cent.
"The key message of the study is overwhelming: that there's a huge shift [from infectious diseases] towards chronic disease and disabilities," says Professor Peter Piot, director of the London School of Hygiene and Tropical Medicine, which released the report findings last month. "In a sense it's actually good news: it's the next stage, it's societal success in a way."
But the advancement that's led to this success has also brought about a new lifestyle: one of little exercise; a diet of processed food that's high in bad fats, sugars and salt; and a growing smoking problem. These lifestyle factors are linked to high blood pressure, diabetes, and raised blood lipids - all direct causes and risk factors for chronic disease.
In Asia, the trend is even more pronounced, says Piot. "Because of much faster economic growth and societal transition in Asia, I think you also find a much faster change in these patterns."
The study estimates that for the first time, shortly after the year 2015, there will be more people above age 65 than below age five globally. For every year of life expectancy that has been added to the average length of life since 1990, it is estimated that less than 10 months is healthy living and the rest is spent in some degree of disability.
This isn't exactly good news for Hongkongers, who are among the longest living people in the world. In 2011, life expectancy was 80.5 years for males and 86.7 years for females - up from 74.6 years and 80.3 years respectively in 1990. In 2041, life expectancy is projected to increase to 84.4 years for males and 90.8 years for females.
"My ambition in life is to live long and die healthy," says Piot, 63, a Belgian native who co-discovered the Ebola virus in 1976, and led research on HIV/Aids, women's health and public health in Africa. "It's not enough to add years to your life, but life to your years."
To do so requires a shift in mindset in society as a whole, he says. This includes reconfiguring and thinking of new ways of health management and dealing with chronic care in the community rather than in the hospital, which Piot says is too expensive.
"Unfortunately, in all countries we are concentrating at the end of the problem: that is, when people have diabetes, or a triple bypass, or cancer. That requires enormous amounts of money," he says.
"We need to treat people, but we also need to think now how we can prevent this kind of unfolding disaster. What's clear is that in every country in the world, health care expenditure is on a train wreck scenario. We can't continue to increase health care expenditure indefinitely."
A key prevention method is by promoting a healthy lifestyle - healthier diets, tobacco control and a culture of exercise - and Piot says societies need to be far more aggressive about this, starting from a young age.
The food industry can help, too, by self-regulating, says Piot. "They're bringing more and more healthy products on the market, but that still represents a tiny percentage of their sales. I think we need to convince the food and beverage industry that they need to produce healthy, inexpensive and tasty food - otherwise people won't eat it."
The societal approach to battling chronic diseases that Piot advocates is based on lessons drawn from his experience dealing with HIV/Aids as the founding executive director of UNAids (the joint United Nations programme on HIV/Aids) and Under-Secretary-General of the UN from 1995 to 2008. "The solution [to HIV/Aids] was not only drugs," he says, "but also a change in behaviour and societal norms."
Piot cites the introduction of "poignant laws and rules" in New York by Mayor Michael Bloomberg as a prime example. By March, sugary soft drinks larger than 473ml will be banned from being sold in restaurants, cinemas and food carts in Manhattan. They'll only be allowed for sale in stores that do not prepare food.
In 2007, Bloomberg's administration also initiated a five-year ban on restaurants using partially hydrogenated vegetable oils and spreads - the main source of trans-fat in the diet.
At the end of the day, simply bombarding the public with health promotion messages isn't going to bring about the desired effect, says Piot.
"I think it's had very, very little impact," he says. "It's not just about messages, but how we deliver the messages. We need to learn from behavioural economics and marketing science."
How many times, for example, have you picked up some candy displayed by the cashier on a whim while checking out at the supermarket?
"That's smart marketing," says Piot. "We're often made to buy things we don't need, or which may even be harmful." So why not turn it around, perhaps by putting fruit at the checkout instead?
In April, Piot will speak at the World Health Summit Regional Meeting in Singapore, and attempt to convince key policymakers in Asia on the urgent need for comprehensive efforts to stem the tide of chronic diseases.
"This is not something only for the Minister of Health or for doctors to do," says Piot. "We need a whole-of-society approach."