Teaching approaches and strategies that promote healthy eating in primary school students: a systematic review and meta-analysis

Background
Achieving optimum nutrition is essential for the healthy growth and development of infants, children and youth. Schools play an essential role in the education and promotion of nutrition and healthy eating among children. The aim of this review was to: 1) perform a systematic review of randomized controlled, quasi-experimental, cluster controlled trials and controlled comparison studies examining school-based interventions that improve the healthy eating outcomes of primary school children through the use of experiential learning pedagogies; 2) perform a meta-analysis to determine the effect of those interventions; and 3) describe the strategies employed that make experiential learning pedagogies effective in terms of primary school students’ learning and behaviour.
Methods
The systematic review was limited to studies that utilised experiential learning pedagogies in order to influence at least one of the following four healthy eating outcomes: 1) reduced food consumption or energy intake; 2) increased fruit and vegetable consumption or preference; 3) reduced sugar consumption or preference (not from whole fruit); and 4) increased nutritional knowledge. Using a university multi-database search engine in July 2015, we searched the 1,166,651 education and health full-text articles published in peer-reviewed journals for controlled or comparative studies that were conducted in primary schools. The search yielded 45,008 possible citations. As search terms were progressively narrowed, abstracts and full texts of articles were screened to determine eligibility. Data pertaining to experiential learning pedagogies that reported on healthy eating outcomes for primary school children was extracted from 13 eligible papers.
Results
There were 12 studies that incorporated experiential learning pedagogies and were associated with small to large effects for reducing food consumption or energy intake; increasing fruit and vegetable consumption or preference; and increasing nutritional knowledge outcomes. Specifically, school gardens, food preparation and cooking programs were identified in the literature as the most dominant manifestations of experiential learning pedagogies implemented in primary schools to promote healthy eating behaviours and knowledge.
Conclusions
Given the finite human and physical resources available to primary schools to promote healthy eating, a meta-analysis of this scope is able to provide schools and policy-makers with the best evidence of where these resources should be focused. This systematic review and meta-analysis suggest that resources including school gardens, food preparation and cooking spaces collectively are effective in promoting healthy eating behaviours and knowledge among primary school aged children, but effectiveness varies based on the number and types of strategies employed.