During the 1990s the prevalence of smoking and the prevalence of obesity in creased among U. S. adolescents. In the Monitoring the Future Study, the percent of twelfth-graders who report having smoked any cigarettes in the last thirty days rose from 28.3 percent in 1991 to 35.1 percent in 1998; similar rises in 30-day prevalence occurred among eighth-graders and tenth-graders [Johnston, 2002]. Data from the National Health and Nutrition Examination Surveys indicates that the prevalence of overweight among 12-19 year olds rose from 10.5 percent to 15.5 percent during the 1990s; a similar rise in prevalence occurred among children aged 6-11. Both of these trends are troubling, because smoking and obesity are among the top causes of preventable death in the United States.
Body weight and smoking are interrelated. Adult smokers weigh less than non smokers and smoking cessation by adults results in an average weight gain of 2-3 kilograms. In contrast, young smokers may be heavier than, or weigh roughly the same as, young non-smokers. This discrepancy may exist because any anorectic effects of smoking are slow to accumulate or because adolescents are more likely than adults to use smoking as a method of weight control.