Evidence synthesis - Neighbourhood retail food outlet access, diet and body mass index in Canada: a systematic review

Abstract

Introduction There is growing interest in the role of food environments in suboptimal diet and overweight and obesity. This review assesses the evidence for the link between the retail food environment, diet quality and body mass index (BMI) in the Canadian population. Methods We conducted a systematic keyword search in two bibliometric databases. We tabulated proportions of conclusive associations for each outcome and exposure of interest. Absolute and relative measures of exposure to the food environment were compared and theoretical framing of the associations noted. We assessed two key methodological issues identified a priori—measurement of BMI, and validation of the underlying retail food environment data. Results Seventeen studies were included in the review. There was little evidence of a food environment–diet quality relationship and modest evidence of a food environment–BMI relationship. Relative measures of the food environment were more often associated with an outcome in the expected direction than absolute measures, but many results were inconclusive. Most studies adopted ecological theoretical frameworks but methodologies were similar regardless of stated theoretical approaches. Self-reported BMI was common and there was no “gold standard” database of food outlets nor a consensus on best ways to validate the data. Conclusion There was limited evidence of a relationship between the food environment and diet quality, but stronger evidence of a relationship between the food environment and BMI for Canadians. Studies with broad geographic scope that adopt innovative methods to measure diet and health outcomes and use relative measures of the food environment derived in geographic information systems are warranted. Consensus on a gold standard food environment database and approaches to its validation would also advance the field.

Associations between the built environment and dietary intake, physical activity, and obesity: A scoping review of reviews

“…Fourteen reviews 26,27,32,[34][35][36][37][38][39][40][41][42][43][44] examined the association of the built environment (e.g., location/presence of food stores and fast-food restaurants) on dietary intake. Across reviews, outcomes focused primarily on fruit and vegetable intake and whether individuals met nutritional guidelines (e.g., recommendations for daily fruit and vegetable or fat consumption).…”

“…Five reviews 27,34,36,37,43 reported support for associations between greater access to supermarkets and higher diet quality (e.g., higher intake of fruits and vegetables, lower intake of saturated fats, or higher overall diet quality index scores) whereas five others (including two reviews focused on natural experiments) 26,27,38,39,41 reported primarily null results. Three reviews 35,37,41 reported significant associations between access to fast-food restaurants and lower diet quality, whereas five others 38,39,[42][43][44] reported primarily null results. In a review of natural experiments, Woodruff and colleagues 32 reported that the opening of a new food retailer (e.g., a supermarket, farmers market, or produce stand) tended to produce some short-term increases in fruit and vegetable consumption in adults who choose to shop at these establishments; however, there was little evidence supporting the longer-term persistence of these effects or of broader community impacts on fruit and vegetable consumption.…”

Associations between the traditional and novel neighbourhood built environment metrics and weight status among Canadian men and women

“…As the groups for ethnicity (non-Whites) were not specific, we did not include ethnicity as a covariate. The original study from which these data were collected investigated relations between the built environment and physical activity (McCormack et al, 2012), thus other built characteristics not available in these data but associated with weight (e.g., food destinations (Stevenson, Brazeau, Dasgupta, & Ross, 2019)) were not included. Our study included mostly established or "built-out" Calgary neighbourhoods that existed in 2007 and 2008.…”

Parental Preconception Exposures to Outdoor Neighbourhood Environments and Adverse Birth Outcomes: A Protocol for a Scoping Review and Evidence Map

“…For instance, neighbourhoods with highly connected streets, high population density and a variety of destinations are associated with higher levels of physical activity and less sedentary behaviour [45] and obesity [45,46]. Tobacco and alcohol outlet density are associated with smoking and alcohol consumption behaviours [47,48], and there is mixed evidence that access to healthy/unhealthy food retail locations is linked to diet and obesity [49][50][51]. Greener neighbourhoods with more parks and vegetation are also linked to higher levels of physical activity [52,53] mental health and wellbeing [52,54], and lower levels of stress [52] and obesity [53].…”