More than 15,000 Scots quit their nicotine habit during the first year of the smoking ban, according to new figures.

And Scotland's Health Minister used the anniversary of the ban yesterday to call for an increase in the legal age at which teenagers can buy tobacco.

Smokers made more than 46,000 attempts to stop over the course of last year, and more than a third of those said they had not fallen off the wagon a month after quitting, according to NHS Scotland.

The figures, released on the first anniversary of the introduction of the ban on smoking in enclosed public spaces, showed that 46,466 addicts contacted smoking cessation services across Scotland between January and December last year.

Meanwhile, the smoking rate dropped to 24.6% for the first three-quarters of 2006, down from 26.2% in 2005.

The figures show the number of smokers attempting to give up was highest during the first four months of the year, and peaked in the run-up to, and immediately following, the ban coming into effect on March 26. In March alone, 8793 attempts were made by smokers to give up nicotine.

Efforts were made to track the progress of 45,641 of the 46,466 attempts to stop made by smokers last year: after one month 15,471 said they had not smoked "even a puff" in the preceding two weeks, meaning 34% had quit.

A further 34% admitted they were still smoking and 32% could not be followed up.

Andy Kerr, the Health Minister, marked the anniversary of the smoking ban by visiting a quitting project in Glasgow, accompanied by Caroline Flint, the Public Health Minister at Westminster.

Mr Kerr said: "It's welcome news that we've got people coming to the health service for support. We're further ahead than we thought we would be. I would now advocate increasing for the age of buying tobacco from 16 to 18."

The figures were welcomed by anti-smoking campaign group ASH. Maureen Moore, chief executive, said: "Reducing the smoking rate was not the aim of the ban, but it is a very welcome side effect.

"But the vital thing is preventing people starting smoking in the first place. We need new measures to stop young people starting smoking."

However, a spokesman for the lobby group Forest, took a different view. He said: "The fall in numbers smoking is roughly in line with what you would expect over the past 30 years, so in that respect the ban has been a failure."

Meanwhile, the final phase of the smoking ban was completed yesterday with the removal of all smoking shelters on NHS premises.

As of yesterday, smokers will no longer be able to smoke in the grounds of hospitals, including the car park areas.

Smoking shelters at all hospitals including Glasgow Royal Infirmary, the Western Infirmary and Gartnavel are no longer available for use.

Glasgow City Council is introducing a similar ban, which will apply to schools and other premises, including the City Chambers.