With Body Mass Index

Childhood obesity has become a critical public health issue inCanada, as rates have tripled over the past three decades.1Over one in four Canadian children are either overweight or obese (17 % and 9 % respectively).2 The increased prevalence of childhood obesity has been linked to the concurrent rise of physi-cal health problems normally associated with adults, including Type 2 diabetes, hypertension, heart disease and pulmonary dis-eases, as well as socio-psychological afflictions such as discrimina-tion, behavioural problems, negative self-esteem, anxiety and depression.3-6 A rapidly expanding avenue of research suggests that rising rates of obesity are due not only to individual-level factors (i.e., genetics), but also to characteristics of our local built envi-ronments that may be encouraging or discouraging the healthy diets or active lifestyles associated with healthy body weights.7-10 Previous research has confirmed that obesity is linked to the con-sumption of energy-rich, fast foods.11 Large-scale US studies have found that adult obesity rates are positively associated with the density of neighbourhood fast-food outlets12 and convenience stores.13 Much of the emphasis on the link between food and chil-dren’s health focuses on advertising14 or food policies within schools;15-17 however, some policy-makers and public health pro-fessionals are shifting their focus to the food environments sur-rounding schools, as new research indicates that many children visit food retailers on their way to and from school, mostly filling up on high-sugar or high-fat, energy-dense foods.18 Several studies have shown that fast-food outlets are more prevalent near schools19,20 and in low-income neighbourhoods,21,22 suggesting that these vulnerable populations may be at heightened risk of devel-oping poor eating habits as a result of increased exposure to unhealthy foods. Furthermore, it has been shown in London, ON