Acute effect of smoking and smoking abstinence on energy intake and appetite-related hormones blood concentrations

The effect of smoking on energy balance and the underlying mechanisms are not fully understood. The aim of the present study is to examine the acute effect of smoking and its abstinence on energy intake, subjective feelings of appetite and related hormones. Fourteen healthy smokers participated in a randomized, crossover study consisting of two trials: the Cigarette trial (participants smoked two cigarettes of their brand within 15 min) and the Sham trial (they were asked to hold the cigarette as smoking, but without lighting it). After 45 min the participants were offered an ad libitum variety of snacks, and their intake was recorded. Blood samples were taken at fasting, before the ad libitum meal and 1 h after and were analyzed for obestatin, ghrelin, glucagon-like peptide-1, cholecystokinin and insulin levels. Subjective feelings of hunger, satiety and desired to eat, as well as smoking craving were evaluated by visual analog scales. Mean energy intake at the ad libitum meal was 825 ± 310 kcal in the Sham trial and 673 ± 245 kcal in the Cigarette trial (p = 0.010). No significant intervention effects were observed for the reported appetite feelings or the appetite-related hormones levels. In conclusion, smoking was found to have an acute effect on dietary intake; this was not explained by changes in the hormonal levels that were evaluated. More research is needed to confirm these results in more prolonged periods of abstinence and explore other pathways through which smoking and its abstinence affect energy balance.