The epidemiology of tobacco use, dependence, and cessation in the United States.

Tobacco use, primarily in the form of cigarette smoking, is the leading preventable cause of death in the United States. After epidemic increases in current smoking in the first half of the 20th century, overall rates of smoking have decreased during the past 30 years. Certain sociodemographic groups continue to have high rates of tobacco use. The prevalence of current smoking in adults in the United States decreased from 42.4% in 1965 to 24.7% in 1995. Recent epidemiologic data indicate that 47 million adults currently smoke cigarettes and over 5 million use smokeless tobacco; over 3 million adolescents are current smokers and over 750,000 use smokeless tobacco. Thus, tobacco use continues to be a major public health concern.