Global rates of smoking are down, but because of population growth the number of people in the world who smoke is up, new research suggests.
Worldwide, about 31 percent of men smoked in 2012, down from about 41 percent of men in 1980. Over the same period, the percentage of women that smoked declined from 10 percent to 6.2 percent.
Because the world population grew in the same period, the total number of smokers increased from 721 million in 1980 to 967 million in 2012, according to the report published today (Jan. 7) in the journal JAMA.
"Despite the tremendous progress made on tobacco control, much more remains to be done," study co-author Dr. Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington, said in a statement. “We have the legal means to support tobacco control, and where we see progress being made we need to look for ways to accelerate that progress."
More than 6 trillion cigarettes were smoked in 2012, researchers found.
To estimate the global smoking rates, researchers analyzed surveys from 187 countries. They found that declines in smoking rates seemed to occur in three phases, with the largest drop in smoking occurring between 1996 and 2006, and smaller drop-offs coming afterwards.
Most of the slowdown in global smoking has come from populous countries such as China and Bangladesh. [ Who Still Smokes? Smokers in the US Today ]
Since 2010, the rates of smoking have increased slightly for men, the researchers said.
Worldwide smoking rates vary greatly by country and gender. Fewer than 1 in 20 women smoke in several African countries, such as Cameroon, Eritrea and Morocco. By contrast, more than a quarter of women smoke in Greece and Austria. More than a half of men are daily smokers in Russia, Indonesia and Armenia.
The nations where smoking's health effects are likely to be most readily seen are China, Ireland, Italy, Japan and Korea, where the high number of smokers also smoke many cigarettes daily. In 75 countries smokers lit an average of more than 20 cigarettes daily in 2012.
A separate study in the same journal found that lower smoking rates in the United States have saved 8 million lives, and increased life span by 19 to 20 years for those who would have smoked, but didn't.
The United States is among several countries where smoking rates declined substantially since 1980, along with Canada, Iceland, Israel, Norway and Sweden, the researchers said.
"Change in tobacco prevalence typically has been slow, underscoring what a hard habit it is to break,” study co-author Emmanuela Gakidou, a global health researcher at the Institute for Health Metrics and Evaluation at the University of Washington, said in a statement. “But we know from these global trends that rapid progress is possible.”
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