"The Healthy Body Image" (HBI) Program: A Program to Promote a Positive Body Image

Too many Norwegian adolescents experience severe body dissatisfaction (40-70 %), and strive to accomplish the "perfect body". At the same time, only 50 % meet the government's recommendations on physical activity and intake of fruits and vegetables. Also, 14-24 % has unhealthy sleeping habits. Optimizing these lifestyle factors is associated with physical and psychological health. These factors, along with the pressure to obtain the "perfect" body, are threatening the adolescent's physical and psychological health, jfr. Meld St nr 19. It is now a need for knowledge on how the investigators can contribute to promote positive body experience among the adolescents.

It has recently, through a controlled study on elite youth athletes at Norwegian sports high schools, been shown that it is possible to change eating habits, improve body image and reduce new cases of eating disorder. It is now desirable to test an adapted program through a school-based program at regular Norwegian high school students (12th grade). Today, no controlled, school-based intervention studies with long-term follow-up have been conducted.

The main aim of this project is to investigate if it is possible, through a school-based intervention program (Healthy Body Intervention), to promote positive body image, increase physical activity level, and healthy eating and sleeping habits in both boys and girls at Norwegian high schools.

The intervention program will contribute with new evidence-based knowledge on the effect of an adapted health-promoting program.

The design is a school-based randomized controlled trial (RCT) intervention, using the methods questionnaire and interview to obtain data. Based on statistical power analyses, all high schools in Oslo and Akershus County will be asked to participate in the study. After the schools have responded, consenting schools will be stratified (by size and geographical affiliation) and randomized to the intervention or the control condition. To minimize contamination biases within schools, the investigators prepare a cluster-randomized design.The population should contain 17-20 schools (1400 students at 2nd year). Data collection is conducted through pre-test and post-test 1, 2, and 3 (acute, 3, and 12 month post-intervention). At post-test 1, a selection is invited to participate in an interview about feasibility in addition to the questionnaire. It is an intervention for students containing interactive lecturers with discussion, team work, discussions and home assignments.

Eligibility Criteria:
Inclusion Criteria:

* Norwegian high schools
* High schools located in either Oslo or Akershus County
* Students in the 2nd grade fall 2016
* Students within academic specialization education programs
* Teachers teaching included students in Norwegian, Social studies, Physical education, and contact teachers
* School nurses working at the randomly selected schools
* School administrators at randomly selected schools

Exclusion Criteria:

* Schools that follow foreign school systems
* Students within vocational education programs
* School departments connected to prison