The objective of this study was to explore nicotine withdrawal symptoms as predictors of increased body mass index (BMI) after an attempt to quit or reduce tobacco smoking. The authors used a survey study, with a probability sample of 4,075 18-64-year-old residents. The participation rate was 70.2%, which included 1,545 current daily smokers. Follow-ups were carried out for current smokers after thirty and 36 months. The authors found that smokers who experienced increased appetite or weight gain (IAW) as a nicotine withdrawal symptom had a higher BMI than smokers without IAW. They concluded that IAW after quitting might be a specific determinant of the BMI increase following smoking cessation in a subgroup of smokers.