From the US Center for Disease Control (CDC)
An estimated 46.2 million adults in the United States smoke cigarettes even though this single behavior will result in death or disability for half of all regular smokers.
Cigarette smoking is responsible for more than 440,000 deaths each year. More than 8.6 million people in the United States have at least one serious illness caused by smoking. If current patterns of smoking persist, 6.4 million people currently younger than 18 will die prematurely from a tobacco-related disease.
Tobacco use is the single most avoidable cause of disease, disability, and death in the United States. Over the past 4 decades, cigarette smoking has caused an estimated 12 million deaths, including 4.1 million deaths from cancer, 5.5 million deaths from cardiovascular diseases, 2.1 million deaths from respiratory diseases, and 94,000 infant deaths related to their mother’s smoking.
Smokeless tobacco, cigars, and pipes also have deadly consequences, including lung, larynx, esophageal, and oral cancer. Low-tar cigarettes and novel tobacco products such as bidis and clove cigarettes are not safe alternatives.
The harmful effects of smoking do not end with the smoker. ... each year, primarily because of exposure to secondhand smoke, an estimated 3,000 nonsmoking Americans die of lung cancer, and more than 35,000 die of heart disease. An estimated 150,000–300,000 children younger than 18 months of age have respiratory tract infections because of exposure to secondhand smoke.
The World Health Organization (WHO) estimates of the number of deaths caused by smoking every year is 4.9 million.