Lung cancer could be virtually wiped out in Scotland as a result of the smoking ban in public places, according to the chief medical officer.
Anecdotal evidence suggests more people may be giving up smoking
Dr Harry Burns said lung cancer rates would be reduced to just a few hundred cases a year in the future.
In 2005, there were 4,000 recorded deaths from lung cancer in Scotland.
His annual report also said there were other signs of improving health, including increased life expectancy, breast feeding and immunisation rates.
Dr Burns said: "Imagining Scotland with no lung cancer is not trivial speculation.
"In the 1960s, one in 100 men died of lung cancer.
"Today, rates are falling all the time and thanks to the smoking ban, I expect the reduction in deaths to accelerate until dying from the disease becomes a rare occurrence.
"Anecdotal evidence shows that since the smoking ban, there has been a surge in the numbers of smokers seeking help to give up."
However, Neil Rafferty, from the Freedom Organisation for the Right to Enjoy Smoking Tobacco (Forest), accused Dr Burns of being irresponsible and painting a "completely misleading picture".
"The evidence from other countries shows that smoking bans have no significant effect on smoking rates," he said.
"Secondly, there is no conclusive evidence that lung cancer is caused by second hand smoke.
"We should really expect better of Dr Burns than to go around making such ludicrous claims."
Mr Rafferty said that by claiming such good results from the policy, the public could be misled into entrusting politicians with more power over people's lives.
Dr Burns said the smoking ban and other public health measures outlined in his annual report were also helping to reduce the incidence of heart disease and strokes.
The latest figures showed that deaths from heart disease fell by 5.2% between 2004 and 2005 and the overall incidence fell by 25% in the past 10 years.
He said: "All the signs show that Scots are starting to take action to help the nation's health turn the corner."