Objective: To assess the efficacy of a peer-led healthy living program on weight gain, and body composition, as well as knowledge of healthy foods and activities when run in a remote isolated community. Design: A non-randomized experimental trial with a parallel non-equivalent control group performed with two student cohorts between January and May in 2011 and 2012 school years. Setting: Kistiganwacheeng Elementary School, Garden Hill First Nation. Participants: A total of 151 students in grades 4 and 5 (41.72% girls). Intervention: The intervention was offered to grade 4 students as a weekly after school program facilitated independently by the high school mentors. Weekly lesson plans focused on four different areas of wellbeing that contribute to health weight: knowledge of healthy living, physical activity, health eating, and social support. Outcome Measures: The primary outcome measures studied were the change in waist circumference and body mass index z-score (BMI z-score). Secondary outcome measures include healthy living knowledge, self efficacy, and body image. Results: Within the entire cohort, 72.67% of the children were overweight or obese. Using a linear mixed effects model with repeated measures (adjusted for weight and time), the increase in waist circumference was significantly less in the intervention group, relative to the control group (+3.4 +/- 1.37 cm vs. 0.39 +/- 0.66 cm; p=0.0001). The BMI z-score increased significantly in the control group (0.07 +/- 0.2 vs. -0.05 +/- 0.03, p=0.199), but was unchanged within the intervention group. There was no significant difference between the groups in post measurement.