Background/Purpose: Little is known about the metabolic outcomes of adolescent bariatric surgery. We report changes in weight, metabolic profile, and types of complications seen in a multicenter cohort. Methods: One-year outcomes were included. For weight loss comparisons, a nonsurgical cohort (n = 12) was used. The primary outcome was weight change (n = 30) and secondary outcomes were metabolic variables (n = 24) and complications (n = 36). Data were analyzed using signed rank or paired t tests. Results: Mean body mass index fell 37% (from 56.5 preoperatively to 35.8 kg/m2; P < .001) in surgical patients and 3% (from 47.2 to 46 kg/m2; P = NS) in nonsurgical patients. Surgical patients showed significant improvements in triglycerides (-65 mg/dL), total cholesterol (-28 mg/dL), fasting blood glucose (-12 mg/dL), and fasting insulin (-21 μM/mL]). Improvement in high-density lipoprotein cholesterol (-3.9 mg/dL) and low-density lipoprotein cholesterol (-8.8 mg/dL) was not statistically significant. Sixty-one percent of surgical patients had no complications. Of 15 patients with complications, 9 had minor complications with no long-term sequelae, 4 had at least 1 moderate complication with sequelae for at least 1 month and 2 had at least 1 severe medical complication with long-term consequences (including beriberi and death). There were no perioperative deaths or other severe surgical complications in this series. Conclusions: Postoperatively, adolescents lose significant weight and realize major metabolic improvements. The complication profile compares favorably to severely obese (body mass index >40 kg/m2) adults; however, small sample size precludes calculation of complication rates. Although there are considerable risks of bariatric surgery, early experience suggests that risks are offset by health benefits. © 2006 Elsevier Inc. All rights reserved.