China's obesity problem is increasing at an "alarming" rate, with nearly 15 percent of the population overweight and a 28-fold increase in the problem in children over the last 15 years, says an editorial in the British Medical Journal.
An increasingly affluent lifestyle with a meatier diet, increased car use and less exercise is responsible for the change, say experts.
But as China's 1.3 billion people pile on the pounds they are storing up problems for the future, such as an epidemic of diabetes and heart disease.
"China was once considered to have one of the leanest populations, but it is fast catching up with the West," wrote Wu Yangfeng (武陽豐) at the Chinese Academy of Medical Sciences in Beijing. "Disturbingly, this has occurred in a remarkably short time."
"It's incredibly dramatic," said Tony Barnett, head of the diabetes and obesity group at Birmingham University. "I think we are seeing this in virtually every country in the world. Interestingly, it is not just the developed world, but increasingly it's the developing world as well."
Wu cited data from China's 2002 national nutrition and health survey, which found that 14.7 percent of Chinese are overweight (184 million people) and 2.6 percent are obese (31 million). This is still a long way off the US, where nearly two-thirds of people are overweight and around a third are obese. Almost half the UK population is overweight.
But the most startling finding is the rate at which China is catching up. The prevalence of overweight and obesity increased 28 times between 1985 and 2000 in children aged seven to 18. Now around one fifth of the overweight or obese people in the world are Chinese.
"People call it westernization, but a lot of it is urbanization," Barnett said. "What goes with urbanization is changes in diet and changes in lifestyle, but particularly exercise. All the evidence that we have is that it is the reduction of activity that is contributing more or at least as much as changes in diet to the epidemic."
There are 20 million cars on the road compared with 6 million in 2000. And people are eating more meat than before. Energy intake from animal sources has shot from 8 percent in 1982 to 25 percent in 2002.
"In Chinese culture there is still a widespread belief that excess body fat represents health and prosperity," Wu said. "This is perhaps a consequence of China's recent history, where famine and chronic malnutrition caused the deaths of millions of people."
China's increasing corpulence is partly behind the world population reaching a dubious milestone. Experts told the International Association of Agricultural Economists conference in Australia this week that there are now many more people overweight than undernourished on the planet.
Around 800 million people are starving worldwide, while more than a billion are overweight.