Effects of policies or interventions that influence the school food environment on children's health and nonhealth outcomes: a systematic review

Trajectories of adherence to an obesogenic dietary pattern and changes in diet quality, food intake, and adiposity during adolescence

BACKGROUND AND AIMS

Contemporary longitudinal data on dietary patterns (DP) during adolescence are scarce. This study aimed to identify trajectories of adherence to an obesogenic DP and changes in diet quality (DQ), related food consumption, and adiposity markers during adolescence.

METHODS

A cohort of 600 adolescents (293 girls, 48.8%) attending 24 secondary schools enrolled on the SI! Program for Secondary Schools trial in Spain was assessed when participants were approximately 12, 14, and 16 years old. An energy-dense, high-fat, and low-fiber (obesogenic) DP was derived at each time point by reduced rank regression (RRR) using the percentage energy intake from fat, fiber density, and dietary energy density as intermediate variables. Based on each participant's resulting scores, trajectories of adherence to the obesogenic DP were identified by latent class trajectory modeling. Adjusted associations between trajectories, DQ and food consumption changes, and adiposity markers during adolescence were analyzed with generalized linear models.

RESULTS

Based on adherence to the obesogenic DP during adolescence, four stable trajectory groups (from lowest to highest adherence) were identified: trajectory 1 (44 participants [7.3%]), trajectory 2 (180 participants [30.0%]), trajectory 3 (292 participants [48.7%]), and trajectory 4 (84 participants [14.0%]). Overall DQ was moderate, but showed a gradient across trajectories, with trajectory 1 having the best quality. Although the identified trajectories were stable, individuals in the group with the lowest adherence to the obesogenic DP (trajectory 1) significantly improved their overall DQ over time, whereas those with the highest adherence (trajectory 4) showed the opposite trend. The group of adolescents in trajectory 4 had the least healthy central adiposity profile when ∼16 years old.

CONCLUSION

Four stable trajectories of adherence to an obesogenic DP were identified in a large cohort of adolescents, with DQ decreasing as adherence to the DP increased. Although adherence to the DP was stable, differences in food intake between trajectories widened over time, resulting in increased central adiposity in participants with the highest adherence to the pattern at the end of the study. Further research is needed to explore the determinants of adherence to obesogenic DPs in adolescence and to evaluate their effects on adiposity and overall health later in life.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03504059.

Method to define recommended portion sizes for consumer guidance

PURPOSE

Provision of nutrition information is mandated for packaged foods, but few countries regulate serving sizes. Our objective was to develop a methodology to establish globally consistent portion size recommendations for both nutrient-dense and discretionary foods.

METHODS

A stepwise systematic approach incorporated portion values from serving size regulations (n = 10), food-based dietary guidelines (FBDG; n = 90, aggregated into 6 regions), and reported food intakes from Europe and Australia. Global Portion Values (GPVs) for 50 food groups were derived as the median of all data inputs. Consistency was evaluated using 25th and 75th percentiles and dispersion of input values (percent of median absolute deviations (MAD)/median).

RESULTS

GPVs were calculated for 50 food groups organized into nine food categories: Milk/Dairy (n = 6 food groups), Protein Foods (n = 5), Mixed Dishes (n = 4), Grains (n = 7), Fruits/Vegetables (n = 5), Snacks/Sweets (n = 12), Sauces/Condiments (n = 5), Fats/Oils/Sugars (n = 4) and Beverages (n = 2). Data inputs for each portion value ranged from 6 to 18; only 4 foods had < 10 inputs; 21 had ≥ 15. Dispersion ranged from 0 to 33%; 88% of GPVs were considered "consistent" (dispersion < 25%) and 9 groups had 0% variation, indicating high consistency. Example GPVs include: 240mL for milk (16 inputs, 8% dispersion); 90 g for meat/poultry/fish main dishes (16 inputs, 13% dispersion); 50 g for bread/rolls (18 inputs, 20% dispersion); 130 g for canned vegetables (10 inputs, 2% dispersion); 30 g for chocolate (15 inputs, 17% dispersion); and 250mL for soft drinks (17 inputs, 20% dispersion).

CONCLUSIONS

This standardized approach provides clear and consistent portion recommendations that, if adopted, could help consumers make informed choices about appropriate portions.

National Policies to Limit Nutrients, Ingredients, or Categories of Concern in School Meals: A Global Scoping Review

The school food environment is a key intervention point for influencing children's and adolescents' diets. As more countries establish school meal programs to provide critical nourishment to students, establishing standards for the foods served can increase the consumption of key nutrients and limit the consumption of foods that do not build health. This global scoping review explores the prevalence and basic characteristics of national policies that regulate food served through school meals across 193 countries, particularly by restricting the provision of categories, nutrients, or ingredients of nutritional concern. We gathered evidence from policy databases, grey literature, peer-reviewed literature, and primary policy documents. We included nationally mandated policies that included restrictions on categories, nutrients, or ingredients of concern served in school meals. Policies that were sub-national, voluntary, and/or did not include restrictive language were excluded from this review. Data was collected in research electronic data capture then extracted into Microsoft Excel and analyzed for policy frequency, prevalence by world region or country income group, and prevalence of certain policy characteristics. Globally, only 15% of countries were found to have a national-level policy restricting foods served through school meals in some capacity, including either nutritional or categorical restrictions. The majority of these policies were found in high-income countries, and no low-income countries had a policy meeting inclusion criteria. Policies in Latin-American and Caribbean countries limited the content of more nutrients of concern than in other regions. Although many policies included explicit guidelines to monitor implementation, few outlined mechanisms for policy enforcement. Future research should evaluate the impact of various school meal regulatory approaches, including implementation of similar policies at sub-national levels, and other elements that affect the impact of school meal programs, such as procurement, infrastructure, costs to school and to students and their families, and acceptability and consumption of foods provided.

Long-Term Effectiveness of a Multi-Strategy Choice Architecture Intervention in Increasing Healthy Food Choices of High-School Students From Online Canteens (Click & Crunch High Schools): Cluster Randomized Controlled Trial

BACKGROUND

School canteens are a recommended setting to influence adolescent nutrition due to their scope to improve student food choices. Online lunch ordering systems ("online canteens") are increasingly used and represent attractive infrastructure to implement choice architecture interventions that nudge users toward healthier food choices. A recent cluster randomized controlled trial demonstrated the short-term effectiveness (2-month follow-up) of a choice architecture intervention to increase the healthiness of foods purchased by high school students from online canteens. However, there is little evidence regarding the long-term effectiveness of choice architecture interventions targeting adolescent food purchases, particularly those delivered online.

OBJECTIVE

This study aimed to determine the long-term effectiveness of a multi-strategy choice architecture intervention embedded within online canteen infrastructure in high schools at a 15-month follow-up.

METHODS

A cluster randomized controlled trial was undertaken with 1331 students (from 9 high schools) in New South Wales, Australia. Schools were randomized to receive the automated choice architecture intervention (including menu labeling, positioning, feedback, and prompting strategies) or the control (standard online ordering). The foods purchased were classified according to the New South Wales Healthy Canteen strategy as either "everyday," "occasional," or "should not be sold." Primary outcomes were the average proportion of "everyday," "occasional," and "should not be sold" items purchased per student. Secondary outcomes were the mean energy, saturated fat, sugar, and sodium content of purchases. Outcomes were assessed using routine data collected by the online canteen.

RESULTS

From baseline to 15-month follow-up, on average, students in the intervention group ordered significantly more "everyday" items (+11.5%, 95% CI 7.3% to 15.6%; P<.001), and significantly fewer "occasional" (-5.4%, 95% CI -9.4% to -1.5%; P=.007) and "should not be sold" items (-6%, 95% CI -9.1% to -2.9%; P<.001), relative to controls. There were no between-group differences over time in the mean energy, saturated fat, sugar, or sodium content of lunch orders.

CONCLUSIONS

Given their longer-term effectiveness, choice architecture interventions delivered via online canteens may represent a promising option for policy makers to support healthy eating among high school students.

TRIAL REGISTRATION

Australian Clinical Trials ACTRN12620001338954, https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=380546 ; Open Science Framework osf.io/h8zfr, https://osf.io/h8zfr/.

Nutrition Interventions for Pediatric Obesity Prevention: An Umbrella Review of Systematic Reviews

Nutrition interventions to prevent pediatric obesity can help to establish healthy habits to improve current and future health. The objective of this umbrella review of systematic reviews (SRs) is to examine the impact of obesity prevention interventions with a nutrition component on body mass index measures, overweight/obesity prevalence, and cost-effectiveness in participants 2-17 years old. Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods were used, and this umbrella review was registered on PROSPERO (CRD42023443033). Included SRs were required to search ≥2 databases and to assess the risk of bias (RoB) of primary studies, and they were published 2017-June 2023. Database searches identified 4776 articles, and 31 SRs were included. In all age groups combined, interventions with both nutrition and physical activity were effective and cost-effective in all settings combined, and in the community setting specifically. In children ≤5 years old, interventions in the home and family, community, and healthcare settings demonstrated some efficacy, whereas in children 6-12 years old, school interventions were most effective. Evidence with individuals 13-17 years was limited. The certainty of evidence was generally low due to RoB in included studies, inconsistency, and imprecision. Pediatric obesity prevention interventions with nutrition should be tailored to the developmental stage to ensure appropriateness and efficacy.