A Systematic Review and Meta-Analysis of Fruit and Vegetable Waste From School Lunch

Abstract

ObjectivesTo synthesize findings from studies that assessed fruit and vegetable (F&V) plate waste from school lunches to i) estimate the level of waste, ii) determine whether there is a difference in F&V waste pre- and post- implementation of the new National School Lunch Program’s (NSLP) meal standards, and iii) identify factors associated with plate waste. MethodsThe systematic review followed the Cochrane Collaboration Guidelines, USDA’s Nutrition Evidence Library (NEL) Bias Assessment, and USDA NEL Conclusion Statement Evaluation Criteria. Meta-analysis of selection and percentage of waste was performed in STATA-16. Thirty-two studies were included in the systematic review and thirty in meta-analysis. ResultsThe estimated mean percentage of students that selected fruits and vegetables were 61% (95% CI: 50%-72%, n = 14), and 48% (95% CI: 37%-59%, n = 14), respectively. The percentage of students who selected fruits increased significantly after the implementation of the new standards. This increase was consistent across all the studies and ranged from 5% to 24%. Fruit waste was estimated to be 39.5% (95% CI: 33.8%–44.5%) and vegetables waste was 50.5% (95% CI: 42.5%–57.4%). No significant differences were found between pre- and post-implementation for fruit or vegetable waste. Child related factors, such as age, gender, and ethnicity/race, were not statistically significant to explain the aggregate waste across studies. Only few studies on plate waste explored the effect of preferences or attitudes, preparation methods, availability of competitive food, and time devoted to eating on F&V waste. However, no relationships could be established beyond the descriptions provided in the original studies. ConclusionsThe change in NSLP meal standards has had a positive effect in increasing the number of students selecting fruits. Further research is warranted to improve the overall F&V selection and reduce waste, especially for dark green vegetables, to maximize the nutritional impact of the NSLP. Funding SourcesUSDA/ARS; The Alliance for Potato Research and Education.