A delegation of health experts from China is visiting Canada this week to learn about anti-smoking laws and get ideas on how to tell China's 350 million smokers to butt out.

Lung cancer is the leading killer of men in the world's most populous country. By 2050, one in three men is expected to die from a smoking-related problem.

As deputy director of the Chinese Centre for Disease Control, Jiang Yuen faces a formidable challenge in a society where smoking is a way of life.

The centre has taken a tentative first step by putting a warning label on cigarette packs, but it is difficult to find the warning, which reads, "Smoking is harmful for your health," rather than "Smoking kills."

"The location is on the inside, not in the front," Jiang said. "And it's very small."

Pro-tobacco forces have the upper hand in China, said Geoff Fong, a psychology professor at the University of Waterloo, and the principal investigator on an international study of tobacco use. The evidence is found in medical offices, where the majority of doctors smoke. 

"Many physicians who happen to smoke don't need to buy cigarettes because their patients provide them with gifts of cigarettes all the time," said Fong, among the Canadians advising the visiting Chinese on everything from warning labels, smoke-free building laws and advertising bans.

Another challenge is that five per cent of government revenue comes from the state-run tobacco business, Jiang said. The China National Tobacco Company controls one-third of the world's tobacco crop.

"The government owns the tobacco industry," said Fong. "We know from conflict-of-interest laws how the presence of a great deal of money can cloud one's judgment with regards to doing the right thing."

Foreign tobacco companies have also identified China as the market with the most growth potential.