The overall objective of this study is to compare the effectiveness of a behavioral, family-based weight management program and a self-help only group for the prevention of obesity in adolescents. The treatments are; Self Help(SH) Instructions to follow a 12-week self help manual for healthy eating and increased physical activity; Intensive Intervention (II) 12 Weeks of daily and 7 Monthly sessions consisting of nutrition instruction, physical activity training, and behavior modification instruction. One hundred (BMI-for-age = 85th - 97.5th % or parent BMI > 25) adolescent males and females will be recruited into the study and randomly assigned to SH) Instructions to follow the self help manual for healthy eating and increased physical activity; II) 12 Weeks daily and 7 Monthly sessions consisting of nutrition instruction, physical activity training, and behavior modification instruction for one year. Participants will receive final measurements at the end of year 1 and intermediate evaluations at month 6. Given that the interventions decline in intensity and frequency after 3 months, the 1 year assessments will help evaluate which treatment was most effective in maintaining weight losses with minimal contact. SH will consist of participants being instructed to follow a 12-week parent/child based self help book for weight loss, but they will not receive any active intervention. The manual (TRIM Kids, Sothern, von Almen, \& Schumacher, 2001) that the families will follow is a treatment program which uses a family-based, behavioral intervention that focuses on diet and exercise with instructions and guidelines designed to assist the family in maintaining weight losses. II will consist of 12 Weeks of daily and 7 Monthly sessions consisting of nutrition instruction, physical activity training, and behavior modification instruction over the 1-year period. Body mass index (BMI), blood analyses (i.e. cholesterol, triglycerides, insulin, glucose, C-reactive protein, mono-unsaturated fatty acids, and inflammatory cytokines), analysis of eating and exercise behavior, and eating and exercise self-efficacy measures will be taken throughout the study. The focus of this study is to evaluate the effectiveness of an active, behaviorally designed intervention for the prevention of adult obesity.
Inclusion Criteria: * Enrolled in the 6th or 7th grade at the target school. * Parent consent and child assent to participate. Exclusion Criteria: * Taking medications for weight control.