School lunch nutritional adequacy: what is served, consumed and wasted.

OBJECTIVE: To determine nutritional adequacy of school lunch and to assess the impact of food waste on nutrient intake of primary schoolchildren. DESIGN: The weighing method was used for evaluating initial servings and plate waste for lunch. Energy and nutritional contents of meals served, consumed and wasted were estimated using the software Food Processor Plus. The mean nutritional value of food served and consumed was compared with dietary guidelines. SETTING: Portuguese public primary schools in the city of Porto. PARTICIPANTS: All 525 fourth-grade children, aged from 9 to 10 years old, attending to twenty-one public primary schools. RESULTS: Overall, school lunches served did not meet the dietary guidelines for energy and nutrients, as only 12·5 % of the evaluated meals were adequate for energy, 33·5 % for proteins, 11·9 % for carbohydrates and 57·1 % for lipids. The majority of meals served were below the age-specific lower limit, namely for energy (83·7 %) and carbohydrates (86·8 %). The only exception, also unbalanced, was observed for proteins, as 42·4 % of lunches served exceeded the recommended upper limit. Furthermore, lunches served and consumed by children did not meet the dietary guidelines for fibre and for the micronutrients evaluated. Children wasted 26 % of the energy content provided in lunches, corresponding to 91·5 kcal, 25 % of proteins and 29 % of carbohydrates supplied. CONCLUSIONS: The lunches served and consumed by children at school canteens failed to meet nutritional standards. These results are not only a consequence of inadequate food portions served but also a result of the high plate waste values observed.

Strategies to reduce plate waste in primary schools - experimental evaluation.

OBJECTIVE: To determine and compare the effect of two interventions in reducing the plate waste of school lunches. DESIGN: A between-group analysis was conducted among children from three primary schools: (i) a group receiving intervention A, designed for children and focusing on nutrition education and food waste; (ii) a group receiving intervention B, intended for teachers and focusing on the causes and consequences of food waste; and (iii) a control group with no intervention. For each child, physical weighing of individual meals and leftovers was performed on three non-consecutive weeks at baseline (T0), 1 week (T1, short term) and 3 months (T2, medium term) following the intervention. Plate waste was recorded for a total of 1742 lunches during 14 d over eight different menus. SETTING: Portuguese public primary schools in the city of Porto. SUBJECTS: All fourth-grade children (n 212) attending the three preselected schools. RESULTS: After intervention A focusing on nutrition education designed for children, a decrease in soup waste was observed compared with the control group. The effect was greater at T1 (-11·9 (se 2·8) %; P<0·001) than at T2 (-5·8 (se 4·4) %; P=0·103). The plate waste of identical main dishes decreased strongly at T1 (-33·9 (se 4·8) %; P<0·001). However, this effect was not found at T2 (-13·7 (se 3·2) %; P<0·001). After intervention B involving teachers, plate waste decreased at T2 (-5·5 (se 1·9) % for soup; -5·4 (se 2·4) % for identical main dishes). CONCLUSIONS: Nutrition education designed for children was more effective in the short than the medium term. Thus, this kind of intervention was not effective in reducing food waste in the medium term. In contrast, an intervention focusing on teachers revealed better results in the medium term than in the short term.