"Tobacco use continues to be the leading global cause of preventable death. It kills nearly 6 million people and causes hundreds of billions of dollars of economic damage worldwide each year. Most of these deaths occur in low- and middle-income countries, and this disparity is expected to widen further over the next several decades. If current trends continue, by 2030 tobacco will kill more than 8 million people worldwide each year, with 80% of these premature deaths among people living in low- and middle-income countries. Over the course of the 21st century, tobacco use could kill a billion people or more unless urgent action is taken."

Source

World Health Organization, "WHO Report on the Global Tobacco Epidemic, 2011: Warning About the Dangers of Tobacco" (Geneva, Switzerland: WHO, 2011), p. 8.
http://whqlibdoc.who.int/publ…