An examination of the associations between walkable neighbourhoods and obesity and self-rated health in Canadians.

BACKGROUND: Two-thirds of Canadian adults and one-third of Canadian children and youth are overweight or obese. There is increased interest in identifying features of the built environment-such as walkability-that facilitate lifestyle habits associated with reduced obesity and improved health. The purpose of this study is to examine how the associations between walkability and both obesity and self-rated health vary by age in Canadians using a new walkability dataset. DATA AND METHODS: The 2016 Canadian Active Living Environments (Can-ALE) database was attached to Canadian Health Measures Survey (CHMS; 2009 to 2015) data. Moderate-to-vigorous physical activity (MVPA), light physical activity (LPA) and step counts were measured in the CHMS using the Actical accelerometer (n = 10,852; ages 3 to 79). Body mass index (BMI) and waist circumference were measured in a mobile clinic. Self-rated general and mental health were assessed using a questionnaire. RESULTS: The percentage of adults aged 40 to 59 classified as overweight or obese was 28 percentage points lower in the most walkable Can-ALE category than in the least walkable category (49.1% vs. 77.5%, p ⟨ 0.0125). There was a significant downward linear trend in measured BMI and waist circumference across Can-ALE categories (from least to most walkable) for adults aged 18 to 59, but not for children and youth or older adults aged 60 to 79. MVPA was a significant mediating factor in the association between the Can-ALE index and BMI in adults aged 40 to 79 (and in the waist circumference of respondents aged 40 to 59). Young adults (aged 18 to 39) were more likely than older adults (aged 60 to 79) to report very good or excellent general health as walkability increased. DISCUSSION: Using a new and freely-available Canadian walkability index, this study observed a positive association between walkability and both measured obesity and self-rated general health in adults. Walkability is one of many built environment characteristics that should be considered when trying to understand the relative contribution of the built environment to a person's weight and overall health.