, 2008). Even among daily smokers, cigarette consumption has been dropping (e.g., Burns, Major, & Shanks, 2003), and it seems likely that the prevalence of very light smoking is increasing, too. LITS now constitute a substantial and important part of the www.selleckchem.com/products/Imatinib(STI571).html smoking population. According to the 2002 NSDUH (Office of Applied Studies, 2003), half of U.S. adult smokers either smoke less than daily (35%) or smoke daily 5 or fewer cigarettes per day (15%). This represents an astounding change in smoking patterns or at least in our understanding of them. Why would light and intermittent smoking suddenly emerge so strongly at this time in U.S. history? One potential influence is the late-20th-century increase in tobacco control activity, including denormalization of smoking and increasing restrictions on smoking.

Indeed, when I compared state-by-state variations in LITS prevalence (Husten et al., 1998), I found that LITS prevalence was highest in those states with the strongest tobacco control policies (indoor air quality, taxation, and youth access, as rated by the American Lung Association, 2003; r=.54) and with the lowest overall prevalence of smoking (r=?.77), suggesting that increases in light and intermittent smoking may be driven by increasing restraints on smoking. It is also possible that as the number of daily smokers drops and the number of LITS remains constant, LITS simply become a higher proportion of the remaining smokers. This would imply that current tobacco control efforts preferentially affect daily smokers but not LITS, which would be an interesting finding, indeed.

The emergence of light and intermittent smoking patterns in the United States may seem surprising, but perhaps it should not be. Although U.S. smoking patterns seem to have been dominated by daily smoking, a global view gives a different picture. In many countries��developing countries, in particular��nondaily smoking is a highly prevalent, even dominant, pattern. For example, in Mexico, Drug_discovery Ecuador, and Guatemala, at least two-thirds of smokers are nondaily smokers (World Health Organization [WHO], 2007). (Note that the majority of U.S. Hispanic smokers do not smoke daily; Office of Applied Studies, 2003; Zhu, Sun, Hawkins, Pierce, & Cummings, 2003.) In China, 20% of male smokers and 46% of female smokers are nondaily smokers (WHO, 2007); this amounts to over 50,000,000 people��more than all the smokers in the United States. Worldwide, with 1.25 billion smokers, hundreds of millions of people are LITS (estimating LITS conservatively at 20%).