Billionaire and former New York mayor Michael Bloomberg has taken on causes such as obesity, gun control, smoking and clean energy. (Spencer Platt/Getty Images)

Despite decades of scientific confirmation and reconfirmation that smoking is a menace to your health, the decline of the myth of the Marlboro man, and a World Health Organization treaty on tobacco control signed by 180 countries, we still have a long way to go in the war against tobacco.

While the prevalence of smokers has fallen dramatically in the United States thanks in large part to education campaigns, the big five tobacco companies have found a new market in developing countries. The number of people smoking the leaves globally has remained sky high — 1.1 billion — with an estimated 6 million dying each year from the health effects.

Can Michael Bloomberg make a difference?

The billionaire former mayor of New York has long been a champion of anti-smoking efforts in the United States. He signed into law an act banning smoking in bars and restaurants and increased the tax on cigarettes. In 2006 and 2008, he took his fight global, giving $125 million and then $250 million to help boost the WHO's efforts in low- and middle-income countries. That has made Bloomberg Philanthropies the largest funder of tobacco-control efforts in the developing world.

On Monday, the group announced an additional $360 million commitment to the effort, bringing his total contribution to nearly $1 billion.

Kelly Henning, who leads public health efforts for Bloomberg Philanthropies, said in an interview that the new donation will help expand its previous work, such as getting countries to monitor tobacco use, introduce strong tobacco-control laws, and create mass media campaigns to educate the public about the dangers of tobacco use. The program includes 110 countries, among them China, India, Indonesia and Bangladesh.

To date, the group has worked with 59 countries with a population of nearly 3.5 billion people to introduce tobacco-control laws and policies and with 36 countries to help them create systems to monitor tobacco use and policy implementation. In India, for example, the government now requires graphic health warnings covering 85 percent of both sides of cigarette packages. And Bangladesh has banned tobacco sales to minors.

Henning said there are signs that efforts are starting to pay off.

Sales of cigarettes appear to have leveled off in 2012, with about 200 billion fewer sold in 2014 than in 2010. The biggest single success story may be Turkey; one survey showed that the number of smokers fell by 1.2 million from 2008 to 2012.

Henning said the new donation will allow the anti-tobacco program to add two new focus areas to its work. The first will be to work with countries to introduce tobacco taxes. The second is related to the first, she said: "How can we counter the tobacco industry to help expose the industry pushback?”

"We know we’re not going to match them dollar to dollar but are going to do our best to raise awareness of the harms of tobacco use,” she said.

In August, Margaret Chan, the director of the World Health Organization, named Bloomberg the WHO's global ambassador for noncommunicable diseases. The unpaid, honorary appointment, which lasts for an initial period of two years, finally gives him an official role to do what he has already been doing for a decade: encouraging policies to help people around the world reduce preventable lifestyle factors such as tobacco and alcohol use that can lead to disease and death.

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