When the first Starbucks cafe opened in Beijing last spring, the customers were mainly foreign residents and Western tourists.
Now, especially on Saturday and Sunday afternoons, it is sometimes hard to get a seat, as the tables are filled with Chinese people sipping cafe lattes and nibbling Danish pastries.
Beijing people are adapting fast to Western ways. On Christmas Eve dozens of young people crowded into the South Cathedral, one of Beijing's largest churches, for what a 16-year-old described as "some fun, and to see what Mass is like". Afterwards she and hundreds of other young Chinese revellers packed into the pubs and clubs in the Sanlitun night-life district to celebrate Christmas the way they imagine their Western counterparts do.
In other words they drank lots of calorie-laden alcohol and ate crisps and chips and other fatty bar snacks. It is considered very trendy to eat fast food, and the waistlines of young Beijingers are beginning to respond. At the end of a century when China suffered its worst famine, people are beginning to put on weight, and to worry about it.
The Yingdong Sanitary Weight Loss centre opened its first clinic in Beijing last year and now has a chain of 10 around town, with plump clients queuing to get rid of excess kilos. This is still a country of slim and graceful women but they worry more nowadays about becoming fat.
Glossy magazines are full of diet advice and advertisements for herbal potions with names like "Slim and Pretty" and other aids such as pills, biscuits, pastes, tea, and even a seaweed soap.
Mr Yang Yongqiang, head of the pharmaceutical section in the SciTech Department Store, which sells more than 40 different diet products, said many woman who buy slimming products are not fat at all, but advertising puts pressure on the modern young female to buy expensive items like May Flora diet tea, the top seller among China's weight-control products.
Some of the most alarming cases of obesity are occurring among young boys, who are traditionally spoiled; the term "fatty" is still used as an endearment by old people.
Parents overindulge the "little emperors" of the one-child family and in today's more Westernised Beijing or Shanghai that often means an outing to McDonald's or Dunkin' Donuts.
Take the case of 12-year-old Chen Ran, who visits McDonald's three times a week, drinks up to six 1.5-litre bottles of Coke and eats 30 meat rolls during recess at school every day. The Beijing boy is one of the increasing number of cases of super-fat children which China's leading obesity expert, Prof Ding Zongyi, has come across. "He demonstrates the obesity lifestyle: soft drinks, high-calorie food, television and eating too fast," she said.
In 1983, the number of obese children in China was estimated at 7 per cent. Now it is 20 per cent, and a campaign against fat in children is under way.
Three years ago 16-year-old Geng Hongda of Shanghai was induced to shed 76.5kg at the Shanghai clinic of a weight-reducing scientist, Jiao Donghai, head of the Shanghai Chinese and Western Medicine Obesity Treatment Centre, who advises his clients to eat a good breakfast but light dinner, and take physical exercise.
The biggest challenge to the weight-reducing industry was posed two years ago by 12-year-old Deng Xuejian, who at 174 kg held the record as China's fattest boy. He became an icon for slimmers after he got his weight down to 114 kg in four months, a feat acknowledged by the Guinness Book of Records which hailed him as the world's champion child slimmer.
He is the star patient of the Tianjin Aimin Weight Reduction Centre which treats about 100 children and 400 adults with a regime which combines exercise to burn up calories, acupuncture to quell appetite and counselling against laziness.
Chinese parents are also being advised by experts not to let their children sit in front of television so much. A glance at the statistics in Taiwan, which is the future for Beijing, having adopted modern teenage fads much earlier, shows what a sedentary lifestyle is doing to kids. Up to a quarter of boys aged 8-10 are obese and 13 per cent of girls, according to the most recent Taiwan survey. Long hours spent viewing TV and playing video games were largely blamed.
"It's clear that kids are leading a much more sedentary life than ever before," said Dr Chwang Leh-chii, president of the Chinese Federation of Dieticians' Associations in Business World. "These results provide a wakeup call that our kids need to get up and move. Obesity is one of the most serious health problems facing the youth of Asia."
Along with Big Macs and Danish pastries has come another malaise from the West previously almost unknown in China, anorexia nervosa and bulimia.
More than 20 patients a year are treated by the Yingdong Sanitary Weight Loss Centre in Beijing, compared to about one a year two decades ago.