Altered reward value of carbohydrate snacks for female smokers withdrawn from nicotine

Abstract

Discontinuing nicotine intake usually results in weight gain partially due to heightened energy intake Iirom between-mcal snacks. This experiment tested the hypothesis that the reinforcing value of palatable carbohydrate-rich snacks increases for fernale smokers dur~ng nicotine deprivation. Eighteen smokers and 18 nonsmokers completed a concurrent-schedules operant computer task on two separate days. Sniokers were biovcrified abstinent at the second testing. The operant task allowed participants to earn points rcdccmable for e~ther carbohydrate snacks or money on concurrent variable-ratio schedules of reinforcement. There were five different prohabillties of earning points rcdccmable for snacks (8%, 16%, 25%, 50%, 75%), while the probability of earning points redeemable for inoney remained fixed at 25%. Reward value of snacks was measured by switch point: the reinforcement ratio at which the effort required to earn snacks exceeded their valuc to the respondent, as signified by a shift to working for money. Results showed that siiiokcrs undergoing nicotine deprivation persisted in \vorking for snacks into Icaner reinforcement schedules than nonsmokers (F.026). Furthcr~nore, nicotine deprivation increased smokcrs' allocation of effort to earn snack foods relative to their own behavior when smoking (P.006). Variation in palatability or hunger did not cxplain these differences in snack reward value. Findings indicate that nicotine deprivation is associated with a heightened reward v a l~~e of appealing snack foods for female smokers. O

Effects of smoking cessation on β-cell function, insulin sensitivity, body weight, and appetite

“…Nonsmokers and smokers who are not smoking seem to perceive the sweet taste as more pleasant than smokers (62). Carbohydrate ingestion was linked to central reward centers in behavioral experiments in people undergoing nicotine withdrawal (63). Further studies involving brain imaging will be needed to elucidate the link between carbohydrate ingestion and smoking cessation.…”

Nicotine and cannabinoids: Parallels, contrasts and interactions

“…It is also possible that rimonabant would be useful in preventing the weight gain associated with smoking cessation (Green and Harari, 1995). Increased food intake is the main factor in smoking cessation-induced weight gain (Caan et al, 1996;Eck et al, 1997;Hatsukami et al, 1993;Moffatt and Owens, 1991;Ogden, 1994;Stamford et al, 1986), but weight gain has also been related to changes in metabolic rate (Filozof et al, 2004) and to an increase in the rewarding properties of palatable foods (Lerman et al, 2004;Spring et al, 2003;Stamford et al, 1986). Chronic exposure to nicotine may induce adaptations in the brain reward system that are masked during active smoking, but induce an increase in the reinforcing properties of hedonic foods in abstinent smokers which will subsequently result in an increase in food intake and body weight gain (Bruijnzeel and Gold, 2005;Hodgkins et al, 2004).…”

Altered hypothalamic response to food in smokers

“…It is currently unknown whether smokers also show an altered brain response to palatable foods; however, in rodents, exposure to nicotine or chocolate cues elicits similar c-fos activation patterns, which are a marker of neural activation (27,28). It has also been shown that abstinent smokers display behavioral patterns that are consistent with an enhanced carbohydrate reward during performance of an operant task (29). Hence, it is possible that nicotine addiction may change the reward value of food and, thereby, influence intake.…”