Abstract
Background: Government standards are now in place for children's school meals but not for lunches prepared at home. The aim of this trial is to improve the content of children's packed lunches. Methods: A cluster RCT in 89 primary schools across the UK involving 1291 children, age eight to nine years at baseline. Follow up was 12 months after baseline. A ‘SMART' lunch box intervention programme consisted of food boxes, bag and supporting materials. The main outcome measures were weights of foods and proportion of children provided with sandwiches, fruit, vegetables, dairy food, savoury snacks and confectionery in each packed lunch. Levels of nutrients provided including energy, total fat, saturated fat, protein, non-milk extrinsic sugar, sodium, calcium, iron, folate, zinc, vitamin A and vitamin C. Results: Moderately higher weights of fruit, vegetables, dairy and starchy food and lower weights of savoury snacks were provided to children in the intervention group. Children in the intervention group were provided with slightly higher levels of vitamin A and folate. 11% more children were provided with vegetables/salad in their packed lunch and 13% fewer children were provided with savoury snacks (crisps). Children in the intervention group were more likely to be provided with packed lunches meeting the government school meal standards. Conclusions: The SMART lunch box intervention, targeting both parents and children, led to small improvements in the food and nutrient content of children's packed lunches. Further interventions are required to bring packed lunches in line with the new government standards for school meals.