Fostering Healthy and Sustainable Diets Through School Meals (OPTIMAT Uppsala)
Condition: Food Habits
Study type: Interventional

Summary: 
      School meals have considerable potential to shape children's diets and reduce the climate
      impact of meals. This study applies linear programming for developing and implementing a
      climate friendly, nutritious and affordable school lunch menu. The new menu plan will be
      compared to the baseline menu during a 4-week intervention trial. The outcomes will be food
      waste, consumption, and pupils' satisfaction with the meals before and after introducing the
      new meal plan analyzed by interrupted time series analysis. Our hypothesis is that school
      meals can be optimized to be nutritious and more climate friendly, without negatively
      affecting acceptance, food waste and cost.

      Four primary schools in one Swedish municipality with the same menu plan for all schools will
      participate in the study. Their current meal supply will be recorded in the form of a food
      list including amount and cost of each item over a 4-week period. This list will then be
      optimized with linear programming to be as similar as possible to the baseline diet but with
      a reduction in greenhouse gas emissions of about 30%. No new foods will be introduced and
      none will be removed from the list. Nutritionally adequacy will be ensured by including
      constraints into the model. The optimized food list will be handed to the municipality's meal
      planner and a new menu plan will be developed based on the revised food list. Data on food
      waste and consumption will be collected daily during a baseline period of four weeks, and
      during the four-week intervention period. School lunch satisfaction will be assessed twice
      with an online questionnaire at baseline and during the intervention.
    

Detailed description: 
      For a period of four weeks, during the spring term of 2020, children from four primary
      schools in Uppsala municipality will receive a new school lunch menu plan which has been
      optimized through linear programming to be as similar as possible to the baseline menu while
      having about 30% lower greenhouse gas emissions (GHGE), being nutritionally adequate, and not
      more expensive.

      During the fall of 2019, a meeting was held with the public meal administration in the
      municipality of Uppsala. The research team described the OPTIMAT project, including the
      previously developed strategy for optimizing and implementing more climate friendly lunches
      in schools. Following this meeting, the municipality agreed to take part in the project. The
      municipality's meal planner proposed four primary schools for the study, presently having the
      highest food related GHGE in public meals in the municipality. To be eligible, the
      intervention schools were required to have on-site kitchens as well as being able to provide
      electronic recipes for a standard four-week menu. All proposed schools fulfilled these
      criteria and approved participation.

      Recipes for an original (baseline) four-week school lunch menu plan previously served at the
      recruited schools were obtained through the municipality's electronic meal planning system.
      The foods included and amounts are considered as the baseline food supply. Each food item
      included has a code that can be coupled to the Swedish national food database and a national
      climate database for foods containing life cycle data for each food item. This baseline food
      supply will be optimized using linear programming. The optimized food list, not including new
      foods or excluding any foods from the baseline list, will be handed to the municipality's
      meal planner who develops a new menu plan for the intervention using all foods on the
      optimized list.

      To assess the effect of the new menu plan, data on food waste and consumption will be
      collected daily in each intervention school four weeks before (baseline) as well as during
      the four-week intervention with a one-week brake between measurement periods. Kitchen staff
      will perform daily weighting (using school kitchen scales) of all food prepared in the
      kitchen (prepared food); the share of the prepared food that is not eaten and has to be
      thrown away (serving waste); the share that can be saved (leftover food); and plate waste.
      Total plate waste, plate waste per pupil, serving waste, total consumption, and consumption
      per pupil will be considered as the primary outcomes as they are regarded as directly related
      to the pupils' acceptability of the new menu. Data on school meal satisfaction will also be
      collected through an anonymous online questionnaire at baseline and during the last week of
      the intervention period. Pupils in grade 8 will answer the questionnaire containing ten
      questions related to the school lunch.
    

Intervention name(s): OPTIMAT
Intervention type(s): Other
Intervention description(s): Baseline menue, not optimized
Intervention model: Single Group Assignment
Intervention model description: Four schools from one county Sweden meet inclusion criteria and are eligible to participate in the intervention. These schools will all serve the baseline menu followed by the new menu. Each period will last for four weeks.
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Children; Public meals; Sustainable diets; Agenda 2030; Greenhouse gas emissions