What makes interventions aimed at improving dietary behaviours successful in the secondary school environment? A systematic review of systematic reviews

Determinants, behaviour change techniques and pedagogical approaches used in secondary school-based food and nutrition programmes: a qualitative study of the SWITCH project

BACKGROUND

Food and nutrition programmes at secondary schools have the potential to improve public and planetary health, as they target a wide range of adolescents. Nevertheless, it is currently unclear what mechanisms are underlying such educational interventions in order to aim for behaviour change. This qualitative study therefore aims to identify determinants and behaviour change techniques (BCTs) incorporated in secondary school-based food and nutrition programmes. Better understanding of determinants and BCTs can identify points of improvements to facilitate long-term dietary behaviour change.

METHODS

Fifteen online semi-structured interviews were conducted between November 2021 and January 2022 with representatives of 14 Dutch programmes, supplemented by a document analysis of scientific and grey literature related to the included programmes (e.g., evaluation reports, teacher manuals). Transcripts and literature were analysed deductively, using the terminology of Mechanisms of Action (MOAs) and the BCT Taxonomy v1, followed by an inductive coding phase.

RESULTS

Determinants knowledge (n = 13), skills (n = 12), awareness (n = 9), and beliefs about consequences (n = 7) were identified most, as well as BCTs Knowledge transfer (n = 13), Natural consequences (n = 7) and Goals and planning (n = 5). Inductive coding led to the identification of pedagogical approaches that were considered important for successful delivery of programmes, such as the use of activating learning methods.

CONCLUSIONS

It seems promising for food and nutrition programmes at secondary schools to expand their current focus beyond knowledge and skills, to also target environmental, social and other essential individual determinants during adolescence which are now under-reported, such as identity. Moreover, our study revealed the importance for programmes to be tailored to adolescents' worldviews and to stimulate adolescents to be actively involved.

Global parent perspectives on school food service internationally: A mixed papers narrative review

AIMS

The views of parents/caregivers about food programs in schools internationally is not well understood. This review aimed to synthesise what parents/caregivers identify as the key features of school food programs and their perspectives of these programs globally.

METHODS

A mixed papers review was undertaken with a systematic search (January 2024) and screening of three databases (Scopus, Web of Science, PubMed). Eligible studies captured parent/caregiver perspectives across all school food models. Study findings were extracted using Bayesian methods to translate quantitative findings into qualitative data. Data was deductively categorised to identify features of school food models, and separately themed to identify parent perspectives.

RESULTS

Twenty-six eligible studies were identified from 11 countries. Fifteen features were identified, including cost, time, effort and convenience, child preferences, nutrition, policy and messaging, eating environment and food education. Parent perspective themes were: child is the priority, lunchbox procurement, preparation and provision is challenging, school-provided meals have strengths and limitations, and parents acknowledge they are central to feeding. An overarching theme was that compromises must be made to meet the needs of family members, when parents make decisions on school food.

CONCLUSIONS

This review found that globally parents perceive benefits and challenges to school food programs, regardless of provision model, with a range of features that influence parent acceptability. Considering parent/caregiver perspectives when developing or changing school food provision models is likely to increase caregiver acceptability, supporting children to engage with health promotion efforts.

Toward Sustainable Diets-Interventions and Perceptions Among Adolescents: A Scoping Review

Adolescence is an important life stage during which shifts toward more healthy and sustainable diets can be promoted. Adolescents have increasing influence over their food choices, informed by their developing personal knowledge and values, affecting long-term dietary behaviors into adulthood. The recent literature regarding adolescents' (1) perceptions of environmentally sustainable diets and (2) interventions to support adolescents to eat sustainably was reviewed in this study. We reviewed published literature that focused on adolescent participants and their perceptions of, or interventions to support, sustainable dietary habits. Five electronic databases were searched to include studies published since 2012 that met the inclusion criteria, including reporting of participants aged between 11 and 18 years, reporting on adolescents' perceptions of sustainable diets or interventions implemented to improve the sustainability of adolescents' diets, and framed in the context of sustainability. Data were extracted, including study and participant characteristics, methodology, and results in relation to each of the 2 research focus areas. Twenty-eight articles were included in the review. Findings suggest that adolescents' understanding of what constitutes sustainable eating is poor. Adolescents who had previously received education regarding sustainable diets valued nature and health, or were from a rural or indigenous community, were more likely to value environmentally sustainable-food choices. Interventions which target adolescents' understanding of and aspiration to make sustainable-food choices appears to improve their attitudes toward sustainable food, whereas interventions to increase the availability of sustainable foods improved the environmental sustainability of adolescents' dietary intake. Multicomponent, tailored, and community-based interventions were most effective; however, the long-term effect of these interventions remains unclear. More research is needed in low- and middle-income countries, with consideration of adolescents' level of autonomy in food choice in local food environments and the long-term effectiveness of interventions. Systematic Review Registration: Open Science Framework identifier osf.io/h3jz6.

Facilitators and barriers to healthful eating among adolescents in high-income countries: A mixed-methods systematic review

Adolescent obesity continues to be a public health challenge with poor quality diets contributing to its etiology. As part of the process to plan health promotion and policy interventions, understanding adolescents perceived facilitators and barriers to healthful eating is important. An integrative convergent mixed-methods systematic review was used to synthesize qualitative and quantitative evidence from studies among adolescents aged 10-19 years in high-income countries. Medline, Embase, PsycInfo, and Scopus were searched for peer-reviewed articles published between 2010 and 2023 and exploring adolescents' perspectives on healthful eating and contemporary contextual factors. Transformed quantitative data were integrated with qualitative data. Text was coded into subthemes and themes using an inductive approach. Key facilitators included health and physical appearance; motivation; taste; nutrition knowledge, awareness, and skills; nutrition education access; availability and accessibility of healthful foods; family; and social influences and digital media. Key barriers included taste and cravings for unhealthful foods; mood; lack of motivation, awareness, knowledge, and skills; high availability and low cost of unhealthful foods; peers and social influences; ineffective school policies; high density of fast-food outlets; unhealthful food advertising; digital influences; and time constraints. Social, behavioral, digital, and food environmental factors should be considered from an adolescent perspective in the design of education, health promotion, and policy interventions.

Effectiveness of nutrition interventions in Australian secondary schools: A systematic review

ISSUE ADDRESSED

Dietary intake of Australian adolescents is suboptimal. Schools are an ideal setting for health promotion initiatives to develop healthy lifestyle behaviours among adolescents. However, we do not know which nutrition-focused, school-based interventions are effective at improving health outcomes in adolescents in Australia. Therefore, the aim was to evaluate the effect of nutrition interventions on health outcomes in Australian secondary school students.

METHODS

MEDLINE, EMBASE, CINAHL, ERIC and Informit were systematically searched on 4th November 2022. Studies in any language evaluating nutrition interventions implemented in Australian secondary schools were included. Studies evaluating interventions conducted in primary schools or outside the school setting were excluded, as were any grey literature, systematic reviews and meta-analyses. Screening and data extraction were performed in duplicate. Quality was assessed using the Mixed Methods Appraisal Tool.

RESULTS

Thirteen studies (n = 27 224) reporting on nutrition interventions implemented in Australian secondary schools were included. Studies were conducted in five different states and a capital territory within Australia and were mostly randomised controlled trials. Most studies reported a significant improvement on nutrition-related health outcome measures (dietary behaviour n = 6, nutritional knowledge and attitudes n = 4 and anthropometric n = 1).

CONCLUSIONS

This review found limited studies reporting on nutrition interventions in Australian secondary schools. However, most were shown to be effective in improving nutrition-related health outcomes. SO WHAT?: Since there were limited studies in peer-reviewed journals, more research in this area is needed to confirm the effectiveness of nutrition interventions in Australian secondary schools and to assess long-term effects on student's health outcomes.

Fruit and vegetable consumption as a preventative strategy for non-communicable diseases

A high intake of fruit and vegetables (FV) has consistently been associated with a reduced risk of a number of non-communicable diseases. This evidence base is largely from prospective cohort studies, with meta-analyses demonstrating an association between increased FV intake and reduced risk of both CHD and stroke, although the evidence is less certain for cancer and diabetes. Controlled intervention trials examining either clinical or intermediate risk factor endpoints are more scarce. Therefore, evidence that FV consumption reduces the risk of disease is so far largely confined to observational epidemiology, which is hampered by some methodological uncertainties. Although increased FV intake is promoted across all dietary guidelines, national surveys confirm that dietary intakes are suboptimal and are not increasing over time. A range of barriers to increasing FV intake exist, including economic, physical and behavioural barriers that must be considered when exploring potential opportunities to change this, considering the feasibility of different approaches to encourage increased FV consumption. Such interventions must include consideration of context, for example, challenges and uncertainties which exist with the whole food system.

Improving adolescents' dietary behaviours in the school-setting: challenges and opportunities

Adolescence is a critical time of physical, psychological and social development, and thus, optimal nutritional intakes are required during this life stage. Despite this, adolescence is recognised as a period of nutritional vulnerability, with many reportedly failing to meet current dietary guidelines. The school-setting presents a favourable environment to intervene and promote positive dietary behaviours and is also inclusive regardless of socio-economic status. However, a lack of consensus exists on how best to utilise schools to facilitate improvements in dietary behaviours among this age group. Whilst previous research has focused on identifying the factors motivating dietary choices within the school-setting, less is known on the optimum strategies to enhance these dietary choices which could positively contribute to the design of future interventions. It is reported that adolescents have good nutritional knowledge, although this does not appear to be a central consideration when making their dietary choices. Alternative factors at the individual (taste, visual appeal, familiarity, food quality, price, portion size, value for money, time/ convenience), social (peer influence), physical (product placement) and macro environment (food availability) levels have been frequently cited as important influences on adolescents' dietary choices in school. Although school-based interventions have shown potential in achieving positive dietary change among adolescents, more research is needed to determine the most effective methods in improving dietary behaviours in schools. This review summarises the key factors which influence adolescents' school-based dietary choices and the effectiveness of previously conducted interventions, identifying promising components for consideration when developing future dietary interventions within the school-setting.

A Qualitative Evaluation of Social Aspects of Sugar-Rich Food and Drink Intake and Parental Strategies for Reductions

Danish children have a much larger intake of sugar-rich foods and drinks than recommended. This study aimed to (1) explore social aspects and practices of pre-school children's intake of sugar-rich foods and drinks and (2) evaluate barriers and parental strategies to reduce their children's intake of sugar-rich foods and drinks employed in connection with the 3.5-month family-centred intervention trial 'Are you too sweet?'. Intervention components included communication of the recommended maximum intake and reduction strategies, supported by resources encouraging and facilitating behavioural changes. A random sample of families (n = 24) from intervention schools participated in post-intervention semi-structured interviews. A thematic content analysis was conducted, revealing three main domains of social practices: (1) 'family treats', including the weekly Danish concept 'Friday sweets', (2) 'everyday treats', such as sweet snacks in lunch packs, between-meals snacks and soft drink habits and (3) 'socialized treats', including treats at special occasions. Parents employed several strategies, most often substitution and portion-size reduction, but also limiting home availability. Families most frequently made changes that were easily adoptable and close to existing routines at home. In conclusion, the intervention components provided families with knowledge and strategies that facilitated behavioural changes towards reducing the intake of sugar-rich foods and drinks.