To characterise children’s lunchbox contents for food, waste, and packaging.

A cross-sectional study was conducted. Lunchboxes were photographed at two time points on the same day: before first morning break to capture food and packaging and post-lunch break to capture food waste. Contents were coded using an audit tool developed using REDCap.

23 sites across metropolitan Adelaide, South Australia including 14 preschools and 9 primary schools in low (n=8), medium (n=7), and high (n=8) socioeconomic areas.

Preschool (3-5 years) to Grade 7 (6-13 years) school students.

673 lunchboxes were analysed. Grain foods dominated (with at least half of them being discretionary varieties), with 92% of lunchboxes having at least one item from that category, followed by fruits (78%), snacks (62%), dairy (32%), and vegetables (26%). Lunchboxes of preschool children contained more fruits (92% vs 65%; χ2(1)=73.3, P<0.01), vegetables (36% vs 16%; χ2(1)=34.0, P<0.01), and dairy items (45% vs 19%; χ2(1)=53.6, P<0.01), compared to lunchboxes of primary school children. Snack foods were more prevalent in primary school (68%) than preschool (55%; χ2(1)=11.2, P<0.01). Discretionary foods appeared more frequently, and single-use packaging accounted for half (53%) of all packaging in lunchboxes, primarily from snacks and grain foods. Preschool children had less single-use packaging but more food waste. Vegetables were the most wasted food group.

Sandwiches, fruits, and various snacks are typical lunchbox foods, often accompanied by single-use packaging. Considering both health and environmental factors in lunchbox choices could benefit children and sustainability efforts in schools.