Younger Elementary School Students Waste More School Lunch Foods than Older Elementary School Students.

BACKGROUND
Children may not receive nutritional benefits from school lunch meals if they do not eat the foods served.

OBJECTIVE
This study investigated whether there were differences in school lunch foods consumed and wasted by grade level of elementary school students.

DESIGN
In this cross-sectional study, anonymous meal observations were conducted after students selected their reimbursable school lunch meals in the cafeteria lunch line. The amounts of foods selected and consumed were recorded using the quarter waste method and food waste was calculated using the information recorded.

PARTICIPANTS/SETTING
During the spring of 2013, eight elementary schools (50% low income) enrolling children in kindergarten through grade 5 in one school district in the Houston, TX, area were selected by the Child Nutrition Director.

MAIN OUTCOME MEASURES
The amount of calories and foods consumed and the percentage wasted were assessed.

STATISTICAL ANALYSES PERFORMED
Analysis of covariance and post hoc analysis were used to examine food consumption and plate waste by grade level (kindergarten and grade 1 [K-Gr1], grades 2 and 3 [Gr2-3], and grades 4 and 5 [Gr4-5]), controlling for student sex and school-level free/reduced priced meal eligibility.

RESULTS
There were 568 nonrandom lunch meal observations of students included in the analyses. Approximately 48% of the observations were from boys; 50% were from low-income schools, and were evenly divided by grade. In general, students in K-Gr1 consumed fewer calories than both Gr2-3 and Gr4-5, and Gr2-3 students consumed significantly fewer calories than Gr4-5. K-Gr1 students also consumed less and wasted more total and red-orange vegetables, total/whole/refined grains, and total protein foods than the older students. Gr2-3 students wasted more calories and total grains than Gr4-5 students. K-Gr1 students wasted more fruit than Gr2-3 students.

CONCLUSIONS
Overall, younger students in elementary schools (K-Gr-1) consumed less of the foods they selected for their lunch meals, and wasted more than older elementary school students. Future studies should investigate why younger children wasted more food and potential strategies to reduce food waste by younger students.