Background: Family-based lifestyle intervention programmes have been known to reduce overweight and improve cardiovascular risk in adolescent obesity [1]. This study was designed to address the gap in service provision of a family based weight management program for overweight and obese adolescents. The LITE (Lifestyle Intervention for obese teenagers) group program is a 6-month, family-based behavioural lifestyle intervention, specifically designed to treat obesity in adolescents 10-16 years referred to the Weight Management Clinic. The main principles underpinning LITE program are that parents are identified as the agents of change responsible for implementing lifestyle change in the family .

Methods: The study design is a two-arm randomized controlled trial that recruited 60 overweight and obese adolescents 10-16 year olds that attended Kandang Kerbau Women and Children's Hospital(KKH) weight management clinic. Adolescents with secondary cause for obesity are excluded. Participants are randomized to LITE program with usual care or usual care.

Briefly, the LITE program involves four x 180 min weekly sessions, followed by three x 90 min monthly sessions, for adolescents and parents. The key aspects covered in the LITE program are in keeping with Health Promotion Board guidelines for the management of overweight and obesity and include healthy food choices and eating patterns, increasing physical activity and reducing sedentary behavior. The parenting aspects aim to support and increase parental capacity to implement and maintain the lifestyle changes. The program takes a solution focused approach with families identifying small changes that they would like to try each week instead of a child-centric approach.

Outcome measurement are assessed at 3 and 6 months post baseline and include anthropometric measurements, physical activity, dietary intake, metabolic profile, improvement in positive parenting behaviour and measurement of family support.

Primary outcome is change in body mass index (BMI) z-score at 6 months. Secondary aim is to evaluate the changes in waist-height ratio and fat percentage change and improvement in positive parenting behaviour.

Inclusion Criteria:

• All adolescents aged 10-16 years old who are currently enrolled in the Weight Management Programme

Exclusion Criteria:

• Intellectual disability, significant medical illness that precludes physical activity and significant psychiatric illness
• Secondary cause of obesity
• Taking of medications that can affect weight status
• Poor level of spoken English (adolescent/carer)
• Severe obesity as defined by BMI more than or equal to 40kg/m2
• Sibling who is already participating in the study

No plan to make IPD available to other researchers based on the informed consent form

Staff involved in anthropometric measurements will be masked to group allocation.