Picture adverts could soon be used in the UK
Under a new EU directive, similar picture warnings may arrive on packets in the UK as early as next year.
The new warnings include pictures of a diseased mouth, a lung tumour and a brain after a stroke.
The warnings helped motivate 44% of smokers taking part in the survey to quit smoking.
Among those who tried to stop in 2001, 38% said the new warnings were a factor in motivating them to try to quit.
Ash director Clive Bates said: "If these warnings prompt people to stop and think again, then they will save thousands of lives in the long term.
"It's all about cutting through the denial and getting smokers to confront the desperate reality of cancer, heart disease and emphysema head on.
"We need picture warnings in Britain as soon as possible.
"If ministers are as serious as they say they are about tackling smoking, then Canada has shown this is a cheap and effective way to get the message across."
Stark warnings
The study looked at the effects of advertising on 2,031 Canadian adults, including 633 smokers.
The survey found new warnings made 58% of smokers think more about the health effects of smoking.
Data showed 90% of smokers and 49% of non-smokers had noticed changes to cigarette package warnings since the beginning of 2001.
On one or more occasions, 21% of smokers were tempted to have a cigarette but decided not to because of the new warnings.
Among non-smokers, 48% said the new warnings made them feel better about being a non-smoker.
Manufacturers of cigarettes with more than 2% market share were required to have the warnings on packages as of 23 December 2000.
Manufacturers of remaining brands were required to place the warnings on packages by 26 June 2001.
The study was conducted for the Canadian Cancer Society.