Network meta- analysis revealed that in adolescents , intervention with 2000 mg/day metformin ranked better than other interventions ; however , 1000 mg/day metformin for 3 months may be most suitable for adolescents .
For adults , metformin at doses of 3000 and 1000 mg/day ranked the highest , other than minimeal and lifestyle interventions ; moreover , intervention with 3000 mg/day for 6 months and 1000 mg/day for 0.5 months may be suitable for adults .
Conclusion When considering the efficacy of interventions for losing weight , metformin offers clear advantages for overweight and obese population
Purpose Our aim was to assess the efficacy of metformin for weight loss in overweight and obese people through a systematic review and network meta- analysis and to identify the most suitable dosage and intervention period for using metformin  in adolescents and adults .
Randomized, controlled trial of metformin for obesity and insulin resistance in children and adolescents: improvement in body composition and fasting insulin.
CONTEXT Metformin therapy for adults and children with type 2 diabetes is well established . However , its role in the treatment of insulin resistance and obesity in children and adolescents is less clearly defined . OBJECTIVE We assessed the effect of metformin on body composition and insulin sensitivity in pediatric subjects with exogenous obesity . DESIGN AND SETTING Patients referred to a pediatric endocrine clinic were enrolled in a r and omized , double-blind , crossover trial . PATIENTS Twenty-eight patients ( 13 males ) aged 9 - 18 yr participated in the study . INTERVENTION Patients received metformin ( 1 g twice daily ) and placebo for 6 months , each with a 2-wk washout period . MAIN OUTCOME MEASURES Body composition ( anthropometry , dual-energy x-ray absorptiometry , and abdominal magnetic resonance imaging ) , and insulin sensitivity ( Si ; minimal model , fasting insulin and glucose ) were measured at baseline and 6 and 12 months . RESULTS Mean age of subjects at baseline was 12.5 + /- 2.2 yr , median body mass index z-score 2.54 ( range , 1.93 - 2.85 ) . Metformin had a greater treatment effect over placebo for weight ( -4.35 kg , P = 0.02 ) , body mass index ( -1.26 kg/m(2 ) , P = 0.002 ) , waist circumference ( -2.8 cm , P = 0.003 ) , sc abdominal adipose tissue ( -52.5 cm(2 ) , P = 0.002 ) , and fasting insulin ( -2.2 mU/liter , P = 0.011 ) . Si improved in 45 % of subjects while on metformin and 27 % of subjects while on placebo ( P = 0.21 ) . CONCLUSIONS Metformin therapy for obese insulin-resistant pediatric patients results in significant improvement in body composition and fasting insulin . Although improvement in Si was noted in many individuals , Si was a less useful parameter for analysis of group data , possibly because of effects of variable compliance and changing Si during puberty
Network meta- analysis revealed that in adolescents , intervention with 2000 mg/day metformin ranked better than other interventions ; however , 1000 mg/day metformin for 3 months may be most suitable for adolescents .
For adults , metformin at doses of 3000 and 1000 mg/day ranked the highest , other than minimeal and lifestyle interventions ; moreover , intervention with 3000 mg/day for 6 months and 1000 mg/day for 0.5 months may be suitable for adults .
Conclusion When considering the efficacy of interventions for losing weight , metformin offers clear advantages for overweight and obese population
Purpose Our aim was to assess the efficacy of metformin for weight loss in overweight and obese people through a systematic review and network meta- analysis and to identify the most suitable dosage and intervention period for using metformin  in adolescents and adults .