Smoking rates in Brazil have dropped by half over the past two decades thanks to strict tobacco control policies, according to a study by US and Brazilian researchers published in this week's PLOS Medicine.

Using a modeling simulation study called Brazil SimSmoke, the authors from authors from Lombardi Comprehensive Cancer Center of Georgetown University in Washington DC and the Brazilian National Cancer Institute in Rio de Janeiro, calculated that 46% of the reduction in smoking rates between 1989 and 2010 (34.8% of Brazilian adults smoked in 1989 compared to 18.5% in 2008) was over and above that which would have occurred if the anti-smoking policies had not been implemented. Brazil introduced a cigarette-specific tax in 1990 and began restrictions on cigarette advertizing, put warnings on cigarette packages, and introduced smoke-free air laws in 1996.

Using the Brazil SmokeSim model, the authors found that between 1989 and 2010, almost half of this 46% reduction in smoking rates in Brazil was from tobacco price increases, 14% was from smoke-free air laws, 14% from tobacco marketing restrictions, 8% from tobacco health warnings, 6% from anti-smoking mass media campaigns, and 10% from treatment programs to help people stop smoking.

Furthermore, the authors estimated that as a result of the anti-smoking policies implemented in Brazil, by 2010, around 420,000 deaths from smoking related causes were prevented and looking ahead to 2050, 7 million deaths will have been prevented. And when the authors estimated the effect of even stricter tobacco control policies, such as an increase in tobacco tax, they found that smoking rates would drop by a further 39% between 2010 and 2050 and prevent 1.3 million early deaths.

The authors say: "Brazil provides one of the outstanding public health success stories in reducing deaths due to smoking, and serves as a model for other low and middle income nations. However, a set of stricter policies could further reduce smoking and save many additional lives."

They continue: "Brazil's accomplishments demonstrate that, even for a middle income nation, reducing tobacco use is a ''winnable battle'' that carries huge dividends in terms of reducing mortality and morbidity."

The authors add: "Most of the measures that Brazil has undertaken cost the government limited resources and, in the case of taxes, generate revenue."