Objective  To examine the consumption, leftover, nutrition and diners′ satisfaction of school lunches among primary and secondary school students in Shanghai municipality for providing evidences to develop polices on school lunch improvement by relevant departments.

  Methods  An onsite survey was conducted at 47 primary and secondary schools selected with stratified cluster random sampling in Shanghai during October – November, 2019. The consumptions and leftovers of the school lunches provided in the schools were estimated with bookkeeping and weighing methods. The nutrition supply of the school lunches were evaluated based on Nutrition Guide for Student Meals issued by National Health and Family Planning Commission in 2017 and Chinese Food Composition Table (6th edition). The amount and relevant factors of school lunch leftovers and satisfaction to the lunches were examined among 11 061 students of grade 4 and above with a self-designed questionnaire online.

  Results  For all the school lunches supplied, the median (quartile range) of food amount per meal per student was 724.8 (371.8) grams (g) and the median of leftover amount per meal per student was 69.5 (86.1) g, with a median of 9.2% (7.8%) for the ratio of the food discarded per meal per student. Among the 11 061 students with valid responses, 48.3% (5 321) reported leftovers of school lunches and the proportions of the students reporting leftovers were 31.1% (3423), 20.5% (2 254), and 20.0% (2 200) for vegetables, meats, and staple food, respectively. Being fussy about some food, without palatable food, with too much food being served were among the most frequently listed reasons for having leftovers, which were reported by 35.4% (3 897), 26.0% (2 866), and 12.5% (1 374) of the students, respectively. The school lunch-related intakes of meat, aquatic products, oil, and salt were higher than those recommend in the Nutrition Guide for Student Meals; while, the intake of soybean products was lower. The school lunch-related nutrition supply was higher for energy ratio of fat, protein and iron but lower for energy ratio of carbohydrate, calcium, and vitamin A for the students of various age groups. The proportions of the students reporting satisfactory evaluation on the school lunches served were 77.2% for dining environment, 73.9% for food hygiene, 73.0% for food amount, 66.0% for food matching, and 56.3% for food taste, respectively.

  Conclusion  The supply of meat, aquatic products, oil and salt are excessive but that of soybean products is insufficient in school lunches for primary and secondary school students in Shanghai. Nearly a half of the schoolchildren had leftovers, especially the leftovers of vegetables, when consuming the lunches. The study results suggest that food taste of the school lunches needs to be improved.