Dr. Prabhat Jha, director of the Center for Global Health Research of St. Michael's Hospital, and professor in the Dalla Lana School of Public Health at the University of Toronto, said such a large tax increase would double the street price of cigarettes in some countries and narrow the price gap between the cheapest and most expensive cigarettes.
The high tax would encourage people to stop smoking rather than switch to a cheaper brand and help young people not to start, especially in low- and middle-income countries. In less developed countries the cheapest cigarettes are relatively affordable and smoking rates continue to rise, Jha said.
Raising cigarette taxes is also effective in rich countries -- France halved cigarette consumption between 1990 to 2005 by raising taxes well above inflation, Jha said.
"Death and taxes are inevitable, but they don't need to be in that order," he said in a statement. "A higher tax on tobacco is the single most effective intervention to lower smoking rates and to deter future smokers."
Jha and colleagues said smokers lose an average of 10 years off their lives -- and those who die in middle age lose about 20 years of life expectancy.
"Worldwide, around a half-billion children and adults under the age of 35 are already -- or soon will be -- smokers and on current patterns few will quit," said study co-author Richard Peto of the University of Oxford. "So there's an urgent need for governments to find ways to stop people starting and to help smokers give up. This study demonstrates that tobacco taxes are a hugely powerful lever and potentially a triple win -- reducing the numbers of people who smoke and who die from their addiction, reducing premature deaths from smoking and yet, at the same time, increasing government income."
The findings were published in the New England Journal of Medicine.