Outside the U.S. Consulate in Shenyang, a teacher at Liaoning Normal University who gave her name as Guo prepared to apply for a visa.

WSJ: Parents of China Victim Get U.S. Visas

The study, by a joint team from the US National Jewish Medical and Research Center and University of Colorado, classed normal weight as someone with a body mass index below 25, overweight over 25 but below 30, and obese as 30 and above.

BBC: NEWS | Health | Overweight 'higher asthma risk'