AimTo ascertain to what extent it is possible to stop being obese (to normalize body mass index [BMI], waist circumference [WC] and/or body fat percentage [BFP]). DesignLongitudinal observational and retrospective study. SiteEleven Spanish health centers. ParticipantsMen and women with BMI≥30kg/m2 (n=1246) or general obesity (GO), with WC>102cm and >88cm, respectively (n=2122) or abdominal obesity (AO) and with BFP>25% and >35%, respectively (n=2436) or excess body fat (EBF), from the PEPAF Study cohort of 4927 participants aged 20-80years. Main measurementsData from the PEPAF study at baseline and at 6, 12 and 24months: gender, age, diagnoses of diabetes, hypertension and dyslipidemia, smoking, levels of and compliance with physical activity recommendations, maximum oxygen consumption, weigh, height, WC and three skin-folds (thoracic, umbilical and anterior thigh for men and triceps, suprailiac and anterior thigh for women). ResultsOf 2054 participants with any type of obesity at baseline and valid data at 2years, 240 (11.6%) had normalized all of their obesity diagnostic indexes. 19.5% (95% confidence interval (95%CI: 17.6-21.4) ceased to have EBF, 12.0% (95%CI: 10.4-13.7) ceased to have AO and 10.5% (95%CI: 8.5-12.7) ceased to have GO. ConclusionsObesity differs from other chronic diseases in that it can be «cured» by normalizing the amount of body fat.