Neighbourhood walkability and dietary attributes: effect modification by area-level socio-economic status

Objective: Higher neighbourhood walkability would be expected to contribute to better health, but the relevant evidence is inconsistent. This may be because residents' dietary attributes, which vary with socio-economic status (SES) and influence their health, can be related to walkability. We examined associations of walkability with dietary attributes and potential effect modification by area-level SES. Design: The exposure variable of this cross-sectional study was neighbourhood walkability, calculated using residential density, intersection density and destination density within 1-km street-network buffer around each participant's residence. The outcome variables were dietary patterns (Western, prudent and mixed) and total dietary energy intake, derived from a FFQ. Main and interaction effects with area-level SES were estimated using two-level linear regression models. Setting: Participants were from all states and territories in Australia. Participants: The analytical sample included 3590 participants (54 % women, age range 34 to 86). Results: Walkability was not associated with dietary attributes in the whole sample. However, we found interaction effects of walkability and area-level SES on Western diet scores (P < 0 center dot 001) and total energy intake (P = 0 center dot 012). In low SES areas, higher walkability was associated with higher Western dietary patterns (P = 0 center dot 062) and higher total energy intake (P = 0 center dot 066). In high SES areas, higher walkability was associated with lower Western diet scores (P = 0 center dot 021) and lower total energy intake (P = 0 center dot 058). Conclusions: Higher walkability may not be necessarily conducive to better health in socio-economically disadvantaged areas. Public health initiatives to enhance neighbourhood walkability need to consider food environments and socio-economic contexts.

Automated summary

Higher walkability may be associated with dietary attributes depending on area-level socio-economic status (SES), with higher walkability being related to higher Western diet scores and total energy intake in low SES areas, and lower Western diet scores and total energy intake in high SES areas.