Do childhood excess weight and family food insecurity share common risk factors in the local environment? An examination using a Quebec birth cohort

Childhood excess weight and family food insecurity are food-system related public health problems that exist in Canada. Since both relate to issues of food accessibility, availability and utilization, which have elements of “place”, they may share common risk factors in the local environment that are amenable to intervention. In this area of research, the literature derives mostly from an American context, and there is a dearth of high-quality evidence, specifically from longitudinal studies. The main objectives of this thesis were to examine the adjusted associations between the place factors: material deprivation, social deprivation, social cohesion, disorder, and living location, with change in child body mass index (BMI) Z score and with change in family food insecurity status in a Canadian cohort of children. The Quebec Longitudinal Study of Child Development was used to meet the main objectives of this thesis. Response data from 6 collection cycles (4–10 years of age) were used in 3 main analyses. The first analysis examined change in child BMI Z score as a function of the place factors using mixed models regression. The second analysis examined change in child BMI Z score as a function of place factors using group-based trajectory modeling. The third and final analysis examined change in family food insecurity status as a function of the place factors using generalized estimating equations. Social deprivation, social cohesion and disorder were strongly and positively associated with family food insecurity, increasing the odds by 45%–76%. These place factors, on the other hand, were not consistently associated with child weight status. Material deprivation was not important for either outcome, except for a slight positive association in the mixed models analysis of child weight status. Living location was not important in explaining family food insecurity. On the other hand, it was associated with child weight status in both analyses, but the nature of the relationship is still unclear. Results do not suggest that addressing similar place factors may alleviate both child excess weight and family food insecurity. More high-quality longitudinal and experimental studies are needed to clarify relationships between the local environment and child weight status and family food insecurity.