Resisting tempting foods and smoking behavior: implications from a self-control theory perspective.

Tobacco is the second leading cause of death in the world (World Health Organization, 2006), accounting for about 5 million deaths annually, equivalent to 1 in 10 adults worldwide. In the United States, more than 400,000 people die each year from cigarette smoking. Despite these statistics, concerns over weight gain are often grounds for initiation of smoking behavior, reluctance to quit smoking, and smoking relapse (Gritz & Crane, 1991; Klesges, Meyers, Klesges, & La Vasque, 1989; Perkins, Epstein, Fonte, Mitchell, & Grobe, 1995). Clinical tobacco treatment practice guidelines recommend that individuals concentrate on smoking cessation rather than caloric restriction until they are confident that they will not relapse (Fiore et al., 2008). Studies with animals (e.g., Carroll, Stotz, Kliner, & Meisch, 1984) and humans (e.g., Cheskin, Hess, Henningfield, & Gorelick, 2005; Hall, Tunstall, Vila, & Duffy, 1992) have demonstrated that concurrent dieting may undermine attempts to quit smoking. Hall and colleagues (1992) found that individuals who received either an individualized diet plan intervention or general nutritional educational treatment combined with smoking cessation counseling had higher smoking rates at follow-ups compared with a group receiving only smoking cessation counseling. Similarly, a controlled experiment conducted in an inpatient research ward demonstrated that patients smoked 8% more cigarettes while on a 6-day low-calorie diet compared to their smoking while on a 6-day normal calorie diet (Cheskin et al., 2005). The current study focuses on the importance of self-control to understanding both dieting and smoking behaviors. Self-control is defined as overriding or inhibiting behaviors, urges, or desires that would otherwise interfere with goal directed behavior (Barkley, 1997; Baumeister, Bratslavsky, Muraven, & Tice, 1998). Without self-control, an individual would carry out his or her normal or automatic behavior or engage in immediate, short-term focused actions, unable to delay immediate gratification (Hayes, Gifford, & Ruckstuhl, 1996; Rachlin, 2000) The ability to exert self-control is critical for successful smoking cessation because smoking becomes an automatic pattern of behavior and someone who typically smokes and wishes to quit must exert self-control to resist that urge and break the habit (Brown, 1998; Tiffany, 1990). Similarly, with weight loss efforts, self-control is essential to successfully restrain from eating various foods (Herman & Polivy, 2004). Problem eating, specifically binge eating, has been associated with poor general self-control (Ricciardelli, Williams, & Finemore, 2001). An innovative model of self-control, the self-control strength model (Muraven & Baumeister, 2000) may offer an explanation for the detrimental effects of dietary restraint on smoking behavior. The self-control strength model suggests that individuals have a limited resource, self-control strength, to use for various volitional exertions such as resisting temptations. According to this model, exerting self-control consumes or depletes this resource for a short time and as a result individuals are prone to perform more poorly on subsequent tasks that require self-control. Psychological experiments using a variety of self-control depletion techniques have demonstrated support for the self-control strength model and shown that exerting self-control on one task impairs further performance for a range of subsequent tasks that require self-control (e.g., Baumeister et al., 1998; Vohs & Heatherton, 2000). For instance, a study of social drinkers exposed to the sight and smell of their favorite alcoholic beverage, but instructed to resist drinking it, performed more poorly on a difficult handgrip task and a self-stopping reaction time measure, compared to their performance after resisting water (Muraven & Shmueli, 2006). In another set of studies, participants’ whose self-control strength was depleted were more likely to cheat on a test than those who were not depleted (Muraven, Pogarsky, & Shmueli, 2006; Shmueli & Muraven, 2007). Thus, according to the self-control strength model, two seemingly unrelated tasks that demand inhibition can affect one another because they both require and deplete the same self-control strength or resource. The current study explored the implications of the self-control strength model for the co-occurring self-regulation demands of cigarette smoking and caloric restriction. In the testing paradigm, participants were exposed to tempting foods (e.g., cookies, candy) or raw vegetables and asked to resist eating from them. Previous research indicates that craving for food can be elicited by exposure to food cues, such as the sight and smell of food. Following the self-control strength model, resisting the urge to eat tempting foods should deplete self-control strength and impair subsequent attempts to override the urge to smoke. There is evidence linking food-related cue exposure and subsequent self-control performance in areas other than smoking. Participants who were exposed to but instructed to resist eating from a tempting plate of chocolate chip cookies performed more poorly on a subsequent self-control task of frustration tolerance, compared with a control condition instructed to resist eating radishes (Baumeister et al., 1998). Another study demonstrated that dieters who resisted the temptation of candy were more likely to subsequently break their diet than dieters who did not have to resist that temptation (Heatherton & Vohs, 1997). The current study assessed whether cue exposure involving sweets leads to a greater urge for cigarettes and a greater likelihood of subsequent smoking. We hypothesized that: (a) the task of resisting tempting sweets rather than raw vegetables would deplete participants’ self-control resources leading to a greater likelihood of their smoking during an assigned study break; and (b) participants who resisted tempting sweets would report higher urges to smoke cigarettes than those who resisted raw vegetables. If depletion of self-control strength is the mechanism underlying the detrimental effects of dietary restraint on smoking behavior, the findings will support the current clinical guidelines, which suggest delaying dieting when initially quitting smoking (Fiore et al., 2008) and provide an explanation for why they are important.