Investigating Obesity Related Behaviours in Friendship Networks Among the Youth: A Systemized Review
Background: An unhealthy diet, low levels of physical activity and increased participation in sedentary activities are important obesity-related behaviours that negatively impact the health of today’s youth. Friends’ health behaviours have been found to influence the individual health behaviours; however current evidence on the specific role of friendship networks on obesity-related behaviours are inconclusive. The purpose of this review is to profile the existing literature in an attempt to identify the associations between friendship networks and obesity-related behaviours among adolescents. Method: A systemized review of the literature was undertaken after a search of the Scopus database, a total of fifteen articles were eligible for inclusion. The selected publications assessed the association between friendship networks and obesity-related behaviours (diet, physical activity, and sedentary behaviour) among the youth. Results: There is consistent evidence that friends are similar in physical activity; evidence on diet and sedentary behaviour is mixed and limited. Friendship network characteristics seem to associated with obesity-related behaviours. Popularity (receiving ties) is likely to be associated with diet, network size and the proportion of active friends is tends to be associated with physical activity and finally, network density is associated with sedentary behaviour. Conclusion: Friendships are critical in shaping young people’s obesity-related behaviours. There is extensive research investigating friendship influences on diet physical activity and sedentary behaviour. Future studies should investigate whether friendship influence operates via other obesity-related behaviours that have not been explored yet such as sleep. Results from this review are informative for designing effective public health interventions because network-based promotion interventions have a promising potential.
Keywords: social networks, friendship, diet, physical activity, sedentary behaviour, obesity
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