Legislative approaches to tackling the obesity epidemic

Promoting healthy school food environments and nutrition in Canada: a systematic review of interventions, policies, and programs

CONTEXT

The school food environment is a critical interface for child and adolescent nutrition, and there is a need to understand existing literature on Canadian school food environments to identify equity gaps and opportunities, and empower decision-makers to plan for future action.

OBJECTIVE

Literature on Canadian school food and nutrition interventions, policies, programs, and their effects on diets and nutritional status are synthesized and appraised in this systematic review.

DATA SOURCES

A search strategy was developed for each database used (Medline, Embase, PsycINFO, ERIC, Cochrane Collaboration, Canadian Electronic Library, BiblioMap), with a combination of free text and controlled vocabulary, for articles published from 1990 to 2021. Unpublished data and grey literature were also searched.

DATA EXTRACTION

Quantitative and qualitative studies with an observational or intervention study design, reviews, or program evaluations conducted in Canadian schools with participants aged 5-19.9 years were included. Key study characteristics and risk of bias were extracted independently by 2 investigators using a standardized tool.

DATA ANALYSIS

A total of 298 articles were included (n = 192 peer reviewed and 106 from the grey literature), which were mostly conducted in Ontario (n = 52), British Columbia (n = 43), and Nova Scotia (n = 28). Twenty-four interventions, 5 nonevaluated programs, and 1 policy involved Indigenous populations. Overall, 86 articles measured and reported on effectiveness outcomes, including dietary intake; anthropometry; knowledge, attitudes, and practices; and physical activity. The literature remains largely heterogenous and primarily focused on nutrition education programs that use subjective assessments to infer changes in nutrition. A key facilitator to implementation and sustainability was community engagement, whereas key barriers were staff capacity, access to resources and funding, and consistent leadership.

CONCLUSIONS

This review provides insight into Canadian school food and nutrition interventions, programs, and policies and uncovers important evidence gaps that require careful examination for future evaluations. Governments must create supportive environments that optimize nutrition for children and adolescents through equitable policies and programs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022303255.

Susceptibility to price discounting of soda by neighbourhood educational status: an ecological analysis of disparities in soda consumption using point-of-purchase transaction data in Montreal, Canada

Introduction

Price discounting is a marketing tactic used frequently by food industries and retailers, but the extent to which education modifies the effect of discounting on the purchasing of unhealthy foods has received little attention. We investigated whether there was a differential association of price discounting of soda with store-level soda purchasing records between 2008 and 2013 by store-neighbourhood education in Montreal, Canada.

Methods

Using data on grocery purchase transactions from a sample of supermarkets, pharmacies, supercentres and convenience stores, we performed an ecological time-series analysis, modelling weekly store-level sales of soda as a function of store-level price discounting, store- and neighbourhood-level confounders and an interaction term between discounting and categorical education in the neighbourhood of each store.

Results

Analysis by store type (n = 18 743, 12 437, 3965 and 49 533 store-weeks for superstores, pharmacies, supercentres and convenience stores, respectively) revealed that the effect measure modification of discounting by neighbourhood education on soda purchasing was lower in stores in the more educated neighbourhoods, most notably in pharmacies: -0.020 [95% confidence interval (CI): -0.028, -0.012] and -0.038 (95% CI: -0.051, -0.025), for middle- and high-education categories, respectively). Weaker effect modification was observed in convenience stores. There was no evidence of effect modification in supercentres or superstores.

Conclusions

Price discounting is an important environmental risk factor for soda purchasing and can widen education inequalities in excess sugar intake across levels of education. Interventions to regulate price discounting warrant further investigation as a public health strategy to improve population nutrition, particularly in lower-education neighbourhoods.

Hunger and Obesity as Symptoms of Non-Sustainable Food Systems and Malnutrition

Among the great challenges the world faces are how to ensure food security for its growing population—projected to rise to around 10 billion by 2050—so it can meet their nutritional needs for a healthy life. Current regulations and literature on food security mainly focus on food quantity (i.e., portion sizes), daily calorie intake and methods for increasing food production and too little on food and diet quality and the holistic effects of (mal)nutrition. From a systems perspective, in order to promote innovation policies for more sustainable food systems, food security cannot be viewed independently; rather, it is characterized by the interplay of an extensive network of economic, environmental and social dimensions that should all be taken into account in a comprehensive resilient and sustainable global food system. Here, we highlight one aspect of this vast network that we consider a particular challenge—yet also a great opportunity—for innovative policies geared toward more sustainable food systems: the interplay of hunger and obesity, including resulting policy strategies beyond potential efficiency improvements in farming practices. Future studies need to emphasize the importance of an in-depth understanding of the interdependencies within the global food system and its interrelatedness with societal and natural systems as part of coupled human-environment systems and in the face of continuing population growth and food demand globally. Recommended strategies for achieving sustainable food security systems include innovative educational approaches and stakeholder-driven innovation policies based on mutual learning processes between society, science, industry and policymakers, as well as fostering increased responsibility of all members of society along the agriculture and food value chain.

Association between junk food consumption and fast-food outlet access near school among Quebec secondary-school children: findings from the Quebec Health Survey of High School Students (QHSHSS) 2010-11

OBJECTIVE

We investigated the association between junk food consumption at lunchtime (JCL) and fast-food outlet access near school among secondary-school children in Quebec.

DESIGN

A geographic information system database was used to characterize the food environment around a sub-sample of 374 public schools in which 26 655 students were enrolled. The outcome variable was JCL during the previous week, dichotomized into low JCL (none or once) v. high JCL (twice or more). Access to fast-food outlets near school was assessed using an existing database of fast-food outlets in Quebec. Covariates included student (age, sex and self-rated perceived health), family (familial status and parental education) and school (urban/rural status and deprivation) variables. Hierarchical logistic regression models were employed for analyses using PROC GLIMMIX of SAS version 9.3.

SETTING

Province of Quebec, Canada.

SUBJECTS

We used data from the Quebec Health Survey of High School Students (QHSHSS) 2010-11, a survey of secondary-school Quebec students.

RESULTS

Exposure to two or more fast-food outlets within a radius of 750 m around schools was associated with a higher likelihood of excess JCL (OR=1·50; 95 % CI 1·28, 1·75), controlling for the characteristics of the students, their families and their schools.

CONCLUSIONS

The food environment surrounding schools can constitute a target for interventions to improve food choices among secondary-school children living in the province of Quebec. Transforming environments around schools to promote healthy eating includes modifying zoning regulations that restrict access to fast-food outlets around schools.

Obesity surgery and Ramadan: a prospective analysis of nutritional intake, hunger and satiety and adaptive behaviours during fasting

BACKGROUND

Fasting for religious or lifestyle reasons poses a challenge to people who have undergone bariatric surgery. A total fast (abstaining from all forms of nourishment including liquids) during long summer days puts these patients at risk of dehydration and poor calorie and nutrient intake.

METHODS

We undertook telephone surveys of 24-h food recall, hunger and satiety scores, medication use, adverse symptoms and depression scores on a fasting day in Ramadan and a non-fasting day subsequently.

RESULTS

We studied 207 participants (166 women) who had undergone sleeve gastrectomy. The mean (standard error) age was 35.2 (0.7) years. Men and women consumed 20.4 % (P = 0.018) and 16.9 % (P < 0.001) fewer calories and 44.8 % (P < 0.001) and 32.4 % (P < 0.001) less protein during fasting, respectively. There was no significant difference in the intake of fluids or incidence of adverse gastrointestinal, hypoglycaemic and sympathoadrenal symptoms. Of participants on pharmacotherapy, 89.5 % took their prescribed medications; 86.3 % made no changes to the doses, but 80.4 % changed the timing of the medications. Both women and men reported feeling less hungry and a preference for savoury foods during Ramadan. There was no difference in depression and work impairment scores.

CONCLUSIONS

Fasting was well tolerated in persons who had undergone sleeve gastrectomy. It may be advisable to raise awareness about dietary protein intake and managing medications appropriately during fasting.

Clinical, humanistic, and economic burden of chronic obstructive pulmonary disease (COPD) in Canada: a systematic review

Background

Chronic obstructive pulmonary disease (COPD) is a chronic, irreversible disease and a leading cause of worldwide morbidity and mortality. In Canada, COPD is the fourth leading cause of death. This systematic review was undertaken to update healthcare professionals and decision makers regarding the recent clinical, humanistic and economic burden evidence in Canada.

Methods

A systematic literature search was conducted in PubMed, EMBASE, and Cochrane databases to identify original research published January 2000 through December 2012 on the burden of COPD in Canada. Each search was conducted using controlled vocabulary and key words, with “COPD” as the main search concept and limited to Canadian studies, written in English and involving human subjects. Selected studies included randomized controlled trials, observational studies and systematic reviews/meta-analyses that reported healthcare resource utilization, quality of life and/or healthcare costs.

Results

Of the 972 articles identified through the literature searches, 70 studies were included in this review. These studies were determined to have an overall good quality based on the quality assessment. COPD patients were found to average 0–4 annual emergency department visits, 0.3–1.5 annual hospital visits, and 0.7–5 annual physician visits. Self-care management was found to lessen the overall risk of emergency department (ED) visits, hospitalization and unscheduled physician visits. Additionally, integrated care decreased the mean number of hospitalizations and telephone support reduced the number of annual physician visits. Overall, 60–68 % of COPD patients were found to be inactive and 60–72 % reported activity restriction. Pain was found to negatively correlate with physical activity while breathing difficulties resulted in an inability to leave home and reduced the ability to handle activities of daily living. Evidence indicated that treating COPD improved patients’ overall quality of life. The average total cost per patient ranged between CAN $2444–4391 from a patient perspective to CAN $3910–6693 from a societal perspective. Furthermore, evidence indicated that COPD exacerbations lead to higher costs.

Conclusions

The clinical, humanistic and economic burden of COPD in Canada is substantial. Use of self-care management programs, telephone support, and integrated care may reduce the overall burden to Canadian patients and society.

Long-term effects of 4 popular diets on weight loss and cardiovascular risk factors: a systematic review of randomized controlled trials

BACKGROUND

We conducted a systematic review to examine the efficacy of the Atkins, South Beach, Weight Watchers (WW), and Zone diets, with a particular focus on sustained weight loss at ≥12 months.

METHODS AND RESULTS

We systematically searched MEDLINE, EMBASE, and the Cochrane Library of Clinical Trials to identify randomized controlled trials (RCTs) published in English with follow-up ≥4 weeks that examined the effects of these 4 popular diets on weight loss and cardiovascular risk factors. We identified 12 RCTs (n=2559) with follow-up ≥12 months: 10 versus usual care (5 Atkins, 4 WW, and 1 South Beach) and 2 head-to-head (1 of Atkins, WW, and Zone, and 1 of Atkins, Zone, and control). At 12 months, the 10 RCTs comparing popular diets to usual care revealed that only WW was consistently more efficacious at reducing weight (range of mean changes: -3.5 to -6.0 kg versus -0.8 to -5.4 kg; P<0.05 for 3/4 RCTs). However, the 2 head-to-head RCTs suggest that Atkins (range: -2.1 to -4.7 kg), WW (-3.0 kg), Zone (-1.6 to -3.2 kg), and control (-2.2 kg) all achieved modest long-term weight loss. Twenty-four-month data suggest that weight lost with Atkins or WW is partially regained over time.

CONCLUSIONS

Head-to-head RCTs, providing the most robust evidence available, demonstrated that Atkins, WW, and Zone achieved modest and similar long-term weight loss. Despite millions of dollars spent on popular commercial diets, data are conflicting and insufficient to identify one popular diet as being more beneficial than the others.

Association between neighbourhood fast-food and full-service restaurant density and body mass index: a cross-sectional study of Canadian adults

OBJECTIVE

Frequent fast-food consumption is a well-known risk factor for obesity. This study sought to determine whether the availability of fast-food restaurants has an influence on body mass index (BMI).

METHODS

BMI and individual-level confounding variables were obtained from the 2007-08 Canadian Community Health Survey. Neighbourhood socio-demographic variables were acquired from the 2006 Canadian Census. The geographic locations of all restaurants in Canada were assembled from a validated business registry database. The density of fast-food, full-service and non-chain restaurants per 10,000 individuals was calculated for respondents' forward sortation area. Multivariable regression analyses were conducted to analyze the association between restaurant density and BMI.

RESULTS

Fast-food, full-service and non-chain restaurant density variables were statistically significantly associated with BMI. Fast-food density had a positive association whereas full-service and non-chain restaurant density had a negative association with BMI (additional 10 fast-food restaurants per capita corresponded to a weight increase of 1 kilogram; p&lt;0.001). These associations were primarily found in Canada's major urban jurisdictions.

CONCLUSIONS

This research was the first to investigate the influence of fast-food and full-service restaurant density on BMI using individual-level data from a nationally representative Canadian survey. The finding of a positive association between fast-food restaurant density and BMI suggests that interventions aiming to restrict the availability of fast-food restaurants in local neighbourhoods may be a useful obesity prevention strategy.

A spatial analysis of the association between restaurant density and body mass index in Canadian adults

OBJECTIVE

To investigate the association between fast-food restaurant density and adult body mass index (BMI) in Canada.

METHODS

Individual-level BMI and confounding variables were obtained from the 2007-2008 Canadian Community Health Survey master file. Locations of the fast-food and full-service chain restaurants and other non-chain restaurants were obtained from the 2008 Infogroup Canada business database. Food outlet density (fast-food, full-service and other) per 10,000 population was calculated for each Forward Sortation Area (FSA). Global (Moran's I) and local indicators of spatial autocorrelation of BMI were assessed. Ordinary least squares (OLS) and spatial auto-regressive error (SARE) methods were used to assess the association between local food environment and adult BMI in Canada.

RESULTS

Global and local spatial autocorrelation of BMI were found in our univariate analysis. We found that OLS and SARE estimates were very similar in our multivariate models. An additional fast-food restaurant per 10,000 people at the FSA-level is associated with a 0.022kg/m(2) increase in BMI. On the other hand, other restaurant density is negatively related to BMI.

CONCLUSIONS

Fast-food restaurant density is positively associated with BMI in Canada. Results suggest that restricting availability of fast-food in local neighborhoods may play a role in obesity prevention.

Effects of oleic acid and chicken serum on the expression of adipogenic transcription factors and adipogenic differentiation in hen preadipocytes

We have examined the effect of oleic acid (OA) concentrations and incubation time, along with chicken serum (CS), on adipogenic differentiation and expression of adipogenic transcripts in hen preadipocytes. Preadipocytes were treated with (i) an adipogenic cocktail (DMI) containing 500 nM dexamethasone, 0.5 mM 3-isobutyl-1-methylxanthine and 20 µg/mL insulin alone and DMI + 75, 150, 300 or 600 µM OA for 48 h; (ii) DMI + 300 µM OA (DMIOA) for 6, 12, 24 or 48 h; and (iii) foetal bovine serum (FBS), CS, DMI + FBS, DMI + CS, DMIOA + FBS and DMIOA + CS. While FABP4 was significantly expressed with increasing concentrations of OA, the expression of C/EBPβ, LEPR and FAS were unchanged compared with the control. PPARγ2 expression was unchanged across all time-points. A significantly higher level of C/EBPα was measured at 48 h, but the levels of C/EBPβ increased after 12 h. Levels of FABP4 significantly increased with the time of incubation after 12 h, but that of LPL was reduced (P < 0.05) at 6, 24 and 48 h. FABP4 was highly expressed in cells treated with CS, DMI + CS and DMIOA + CS compared to cells treated with FBS, DMI + FBS and DMIOA + FBS. In conclusion, increased concentrations of OA and incubation time increases lipid accumulation; FABP4 and C/EBPβ are potential transcription factors regulating OA induced adipogenesis of fat cells obtained from laying hen. CS is a potent inducer of adipogenic differentiation in hen preadipocytes.