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 .
Effects of Metformin on Body Weight and Body Composition in Obese Insulin-Resistant Children
OBJECTIVE Metformin can decrease adiposity and ameliorate obesity-related comorbid conditions , including abnormalities in glucose homeostasis in adolescents , but there are few data evaluating the efficacy of metformin  among younger children . Our objective was to determine whether metformin treatment causes weight loss and improves obesity-related comorbidities in obese children , who are insulin-resistant . RESEARCH DESIGN AND METHODS This study was a r and omized double-blind placebo-controlled trial consisting of 100 severely obese ( mean BMI 34.6 ± 6.6 kg/m2 ) insulin-resistant children aged 6–12 years , r and omized to 1,000 mg metformin  ( n = 53 )  or placebo  ( n = 47 ) twice daily for 6 months , followed by open-label metformin treatment  for 6 months . All children and their parents participated in a monthly dietitian-administered weight-reduction program . RESULTS Eighty-five percent completed the 6-month r and omized phase . Children prescribed metformin had significantly greater decreases in BMI ( difference −1.09 kg/m2 , CI −1.87 to −0.31 , P = 0.006 ) , body weight ( difference −3.38 kg , CI −5.2 to −1.57 , P < 0.001 ) , BMI Z score ( difference between metformin and placebo groups −0.07 , CI −0.12 to −0.01 , P = 0.02 ) , and fat mass ( difference −1.40 kg , CI −2.74 to −0.06 , P = 0.04 ) . Fasting plasma glucose ( P = 0.007 ) and homeostasis model assessment ( HOMA ) insulin resistance index ( P = 0.006 ) also improved more in metformin-treated children than in placebo-treated children . Gastrointestinal symptoms were significantly more prevalent in metformin-treated children , which limited maximal tolerated dosage in 17 % . During the 6-month open-label phase , children treated previously with placebo  decreased their BMI Z score ; those treated continuously with metformin did not significantly change BMI Z score further . CONCLUSIONS Metformin had modest but favorable effects on body weight , body composition , and glucose homeostasis in obese insulin-resistant children participating in a low-intensity weight-reduction program
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 .