Anti-smoking measures including higher taxes on tobacco products, bans on adverts and controls on lighting up in public places could prevent tens of millions of premature deaths across the world, researchers said on Monday.

Similar steps taken by Turkey, Romania and 39 other countries between 2007 and 2010 were already saving lives, the independent study published by the World Health Organization (WHO) said.

"If the progress attained by these countries were extended globally, tens of millions of smoking-related deaths could be averted," professor David Levy, the study's lead author from Georgetown University Medical Center in Washington, said in the WHO's monthly bulletin.

Wider use of the controls could also lead to lower health care costs and higher birth weights for babies, he added.

Tobacco-control measures already introduced in the 41 countries, that also included Pakistan, Argentina and Italy, were on track to persuade an estimated 15 million people not to smoke, the study said. That would prevent around 7.4 million smoking-related deaths by 2050, it added.

The researchers found the most effective measures were increasing taxes and banning smoking in offices, restaurants and other public places. The first method would prevent 3.5 million smoking-attributable deaths, while the second would prevent 2.5 million, they said.

"If anything it is an under-estimate," Dr Douglas Bettcher, director of WHO's department of noncommunicable diseases, told Reuters in an interview in his Geneva office.

"It is a win-win situation for health and finance ministries to generate revenues that have a major impact on improving health and productivity," he added.

Turkey's steps led to a sharp drop in smoking rates to 41.5 per cent among men in 2012 from 47.9 per cent in 2008, he said.

Six million people die every year from smoking and the toll is projected to rise to eight million by 2030, according to the WHO, a United Nations agency waging war on "Big Tobacco".

The WHO's Framework Convention on Tobacco Control, which came into force in 2005, lays down measures to curb smoking and tobacco use. About 175 countries have ratified the pact, shunned by others that are home to large tobacco companies, including the United States, Switzerland and Indonesia.

Measures include raising taxes on tobacco products to 75 per cent of the final retail price, smoke-free air policies, warnings on cigarette packages, bans on advertising, promotion and sponsorship, and offering treatments to kick the habit.

"We know that in many poor countries, the poor spend a lot of money on tobacco. They would be able to use it for nutrition and education which is a huge opportunity cost," said Dr Edouard Tursan d'Espaignet, from WHO's Tobacco Free Initiative. - Reuters