title: Overweight prevention in adolescents and children (behavioural and environmental prevention).
abstract: BACKGROUND
  In 2006, the prevalence of overweight and adiposity among children and adolescents aged three to 17 years is 15%, 6.3% (800,000) of these are obese.
  
  
  BACKGROUND
  Obese children and adolescents have an increased body fat ratio. The reasons for overweight are - among others - sociocultural factors, and a low social status as determined by income and educational level of the parents. The consequences of adiposity during childhood are a higher risk of metabolic and cardiovascular diseases and increased mortality in adulthood. Possible approaches to primary prevention in children and adolescents are measures taken in schools and kindergarten, as well as education and involvement of parents. Furthermore, preventive measures geared towards changing environmental and living conditions are of particular importance.
  
  
  OBJECTIVE
  What is the effectiveness and efficiency of different measures and programs (geared towards changing behaviour and environmental and living conditions) for primary prevention of adiposity in children and adolescents, with particular consideration of social aspects?
  
  
  METHODS
  The systematic literature search yielded 1,649 abstracts. Following a two-part selection process with predefined criteria 31 publications were included in the assessment.
  
  
  RESULTS
  The majority of interventions evaluated in primary studies take place in schools. As the measures are mostly multi-disciplinary and the interventions are often not described in detail, no criteria of success for the various interventions can be extrapolated from the reviews assessed. An economic model calculation for Australia, which compares the efficiency of different interventions (although on the basis of low evidence) comes to the conclusion that the intervention with the greatest impact on society is the reduction of TV-ads geared towards children for foods and drinks rich in fat and sugar. There is a significant correlation between adiposity and socioeconomic deprivation. The lack of interventions (especially preventive measures geared towards changing environmental and living conditions) and studies focusing on this population group is noticeable.
  
  
  CONCLUSIONS
  There are only a few primary studies of high quality on adiposity prevention in children and adolescents. Especially studies which compare different measures are lacking. This holds also true for the economic analysis, which seems logical insofar, as the basis for economic analyses are usually primary studies (preferably randomized controlled trials (RCT)) due to their evidence level). Studies on interventions geared towards changing environmental and living conditions and towards specific population groups (i. e. the socially disadvantaged) are hardly available.
  
  
  CONCLUSIONS
  There are hardly any primary studies of high quality on adiposity prevention in children and adolescents, especially studies which compare different measures are lacking. Interventions geared towards specific population groups (particularly for the socioeconomically disadvantaged) are specifically underrepresented. Establishing such studies is an essential requirement of adiposity prevention. Recommended are a combination of measures geared towards changing environmental and living conditions and towards specific population groups. Furthermore, it is recommended to systematically register future programs (preferably online) in order to be able to draft criteria of success.
authors.affiliation: Gesundheit Österreich GmbH, Geschäftsbereich ÖBIG, Wien, Österreich.
authors.forename: Barbara
authors.initials: B
authors.lastname: Fröschl
authors.forename: Charlotte
authors.initials: C
authors.lastname: Wirl
authors.forename: Sabine
authors.initials: S
authors.lastname: Haas