title: Associations of neighbourhood greenness with physical and mental health: do walking, social coherence and local social interaction explain the relationships?
abstract: BACKGROUND
  Studies have shown associations between health indices and access to "green" environments but the underlying mechanisms of this association are not clear.
  
  
  OBJECTIVE
  To examine associations of perceived neighbourhood "greenness" with perceived physical and mental health and to investigate whether walking and social factors account for the relationships.
  
  
  METHODS
  A mailed survey collected the following data from adults (n = 1895) in Adelaide, Australia: physical and mental health scores (12-item short-form health survey); perceived neighbourhood greenness; walking for recreation and for transport; social coherence; local social interaction and sociodemographic variables.
  
  
  RESULTS
  After adjusting for sociodemographic variables, those who perceived their neighbourhood as highly green had 1.37 and 1.60 times higher odds of better physical and mental health, respectively, compared with those who perceived the lowest greenness. Perceived greenness was also correlated with recreational walking and social factors. When walking for recreation and social factors were added to the regression models, recreational walking was a significant predictor of physical health; however, the association between greenness and physical health became non-significant. Recreational walking and social coherence were associated with mental health and the relationship between greenness and mental health remained significant.
  
  
  CONCLUSIONS
  Perceived neighbourhood greenness was more strongly associated with mental health than it was with physical health. Recreational walking seemed to explain the link between greenness and physical health, whereas the relationship between greenness and mental health was only partly accounted for by recreational walking and social coherence. The restorative effects of natural environments may be involved in the residual association of this latter relationship.
authors.affiliation: University of Queensland, Brisbane, Queensland, Australia. t.sugiyama@uq.edu.au
authors.forename: T
authors.initials: T
authors.lastname: Sugiyama
authors.forename: E
authors.initials: E
authors.lastname: Leslie
authors.forename: B
authors.initials: B
authors.lastname: Giles-Corti
authors.forename: N
authors.initials: N
authors.lastname: Owen
mesh_terms: D000328:Adult; D000368:Aged; D004779:Environment Design; D005260:Female; D006304:Health Status; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008603:Mental Health / Q000706:statistics & numerical data*; D008875:Middle Aged; D012111:Residence Characteristics; D012931:Social Environment; D012959:Socioeconomic Factors; D013021:South Australia / Q000453:epidemiology; D014504:Urban Health; D016138:Walking / Q000706:statistics & numerical data*