Psychopharrnacology (1992) 106:53-59 Psychopharmacology © Springer-Verlag 1992 Effects of nicotine on hunger and eating in male and female smokers Kenneth A. Perkins, Leonard H. Epstein, Joan E. Sexton, Rena Solberg-Kassel, Richard L. Stiller, and Rolf G. Jacob Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, 3811 O'Hara Street, Pittsburgh, PA 15213, USA Received July 26, 1990 / Final version May 27, 1991 Abstract. We tested whether the inverse relationship be- tween smoking and body weight may be due in part to nicotine's acute effects on reducing hunger and eating. On four mornings, male and female smokers (n= 10 each), abstinent overnight from smoking and food, re- ceived one of three nicotine doses (7.5, 15, and 30 ~tg/kg) or placebo (0) via nasal spray every 30 rain for 2 h. Self-reported hunger and satiety ("fullness") and craving for cigarettes were obtained after each dose presentation. Subjects subsequently ate ad lib from a large array of food items varying in sweet taste and fat content. For both males and females, nicotine had no effect on self- reported hunger, but cigarette craving was decreased. Rather than being decreased, caloric intake during the meal was unexpectedly increased following nicotine com- pared with placebo. Cigarette craving increased after the meal, and this increase was unaffected by nicotine dose. There were virtually no differences between males and females in any effects of nicotine. These results indicate that nicotine may not acutely suppress appetite in fasting smokers and suggest that other actions of nicotine or smoking may account for the lower body weights of smokers. Key words: Nicotine - Satiety - Hunger - Caloric intake - Craving - Smokers - Males - Females -Sweet taste Cigarette smoking is associated with reduced body weight (USDHHS 1988), an effect which may inhibit attempts to quit smoking or to maintain abstinence after quitting (Pirie et al. 1991). Despite the strength of this inverse relationship between smoking and body weight, its causes remain elusive. Smoking does not increase physical activity (Marks et al. 1991) but does acutely increase metabolic rate (Perkins 1991b). Nevertheless, this effect may not be sufficient to account for smoking's Offprint requests to." K.A. Perkins effect on body weight (Moffatt and Owens 1991), sug- gesting that smoking may also curb appetite. Recently, we found that intake of nicotine versus placebo reduced self-reported hunger in male smokers and nonsmokers following consumption of a caloric pre-load (i.e. in the fed state) and decreased subsequent caloric intake in the nonsmokers (Perkins et al. t991). However, nicotine had no effect on hunger in either smokers or nonsmokers in the fasting state and did not significantly decrease caloric intake in smokers. Thus, nicotine may not uniformly suppress appetite, and such limited effects of nicotine on eating in smokers would suggest that anorectic effects of nicotine may not be very important in explaining lower body weights of smokers. The present study was designed to replicate and ex- tend our previous examination of nicotine's effects on hunger and caloric intake in several ways. First, the previous report examined only males, and the effects of nicotine on hunger and caloric intake in females is not well known. One study suggests that nicotine may de- crease eating among female rats more than it does among males (Grunberg et al. 1987), although the opposite has also been found (McNair and Bryson 1983). Further- more, smoking may have a greater impact on body weights of women compared with men (USDHHS 1988; Williamson et al. 1991). Second, only one nicotine dose was employed in our previous study, and the dose- response relationship between nicotine and hunger or eating remains largely unexplored. A dose-dependent decrease in caloric intake (and body weight) has been reported in rats (e.g. Grunberg 1982), but to our know- ledge there has been no comparable study of caloric intake with humans. Third, it would be important to confirm an absence of nicotine effects on self-reported hunger and eating in the fasting state (Perkins et al. 1991), since it is commonly assumed that nicotine is an anorectic. Therefore, this study explored each of these questions by examining the acute effects of several doses of nicotine versus placebo on hunger and eating in fasting male and female smokers.