Health Effects of Light and Intermittent Smoking

C urrent public health guidelines on the identification and treatment of smokers and the information on the health risks associated with tobacco are based on studies that focus on adult daily cigarette users. 1 Daily smoking, however, is declining, and light and intermittent smoking are increasing.2,3 Light and intermittent smoking are frequently found among young people, educated people, women, 4,5 and minority populations (Hispanics/Latinos, blacks, American Indians, Alaska Natives, Asian Americans, and Pacific Islanders 6 -9 ).Light and intermittent smokers pose a serious challenge to healthcare professionals because they tend not to consider themselves “smokers” and, consequently, are underidentified.10 -13 This propensity not to label oneself as a smoker reinforces the belief that light and intermittent smoking do not carry significant health risks.There is no consensus on how to best define “light smoking.”7,12,14 Light smokers have been classified as smoking Ͻ1 pack per day, Ͻ15 cigarettes per day, Ͻ10 cigarettes per day, and 1 to 39 cigarettes per week.9,14 There are various subgroups of light smokers: low-rate daily smoking (Ͻ5 cigarettes per day), 15 very light smoking (Ͻ6 cigarettes per day), 14,16 and “chippers” who consistently smoke Յ5 cigarettes per day on the days when they do smoke.17 In the past, light smoking has been viewed as a transient practice among former heavier smokers or among tobacco users who are trying to quit.4,5,18 New research, however, shows that some light smokers maintain this consumption pattern indefinitely.11,12,19 Like light smoking, intermittent smoking is a broad term that consists of a variety of patterns of tobacco use but is generally defined as smoking on a nondaily basis.4 -6,8,12,14,20 -22 Social smoking is another example of intermittent smoking, which is characterized by limiting smoking to social contexts, such as parties, bars, or nightclubs.11,12 (Social smokers, unlike other types of intermittent smokers, may never smoke alone.11,23 ) As with light smoking, intermittent smoking is common among minority populations.4,5,8 Black smokers are nearly twice as likely to smoke intermittently (odds ratio, 1.82; 95% confidence interval [CI], 1.59 to 2.07), and Hispanic/Latino smokers are 3 times more likely to smoke intermittently (odds ratio, 3.2; 95% CI, 2.75 to 3.74) than non-Hispanic whites.6 Among young adults, intermittent smoking is frequently From the Center for Tobacco Control Research and Education (R.