Purpose This study aims at investigating prospective associations between body areas satisfaction (BAS), actual (objectively measured)-ideal body weight discrepancy, actual (self-reported)-ideal body weight discrepancy and BMI among adolescents from the general population. Methods Data were collected at three measurement points: baseline (T1), 2-month follow-up (T2), 13-month follow-up (T3) among 1011 adolescents (59.3% girls) aged 13-19 years (M = 16.30, SD = 0.82) with BMIs ranging from 15.20 to 38.78 (M = 20.01, SD = 3.33). Adolescents completed questionnaires regarding BAS (T1), actual and ideal body weight (T2). Body weight and height were measured objectively (T1 and T3). Results Adolescents satisfied with most areas of their bodies had lower levels of actual (objectively measured)-ideal body weight discrepancy, which in turn predicted higher BMI, while lower levels of actual (self-reported)-ideal body weight discrepancy predicted lower BMI. No moderating effect of gender was found. Conclusions Actual-ideal weight discrepancies may operate in complex manner prompting opposite effects on BMI. Level of evidence Level III, longitudinal study without control group.