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School lunch nutritional adequacy: what is served, consumed and wasted
Margarida Liz Martins1,2,3,4,5, Sara Sp Rodrigues1,6, Luís M Cunha4,7,8
1Faculty of Food Science and Nutrition, University of Porto, Porto, Portugal.
Public Health Nutrition
|November 13, 2020
Summary
School lunches in Portugal often fail to meet nutritional guidelines for energy and key nutrients. Significant food waste, particularly of energy, protein, and carbohydrates, further compromises children's nutrient intake.
Area of Science:
- Nutrition Science
- Public Health
- Pediatric Nutrition
Background:
- School lunch programs are critical for providing essential nutrients to primary schoolchildren.
- Assessing the nutritional adequacy of school meals and the impact of food waste is vital for child health.
- Previous studies highlight concerns regarding the nutritional quality of school meals globally.
Purpose of the Study:
- To evaluate the nutritional adequacy of school lunches provided to primary schoolchildren in Porto, Portugal.
- To determine the extent of food waste and its impact on nutrient intake from school lunches.
- To compare the nutrient content of served and consumed school meals against established dietary guidelines.
Main Methods:
- A weighing method was employed to quantify initial food servings and plate waste during school lunch.
- Nutritional content (energy, macronutrients, fiber, micronutrients) of meals was analyzed using specialized software (Food Processor Plus).
- Nutritional values of served and consumed meals were compared with Portuguese dietary guidelines for the target age group.
Main Results:
- School lunches predominantly failed to meet dietary guidelines for energy, protein, carbohydrates, and lipids.
- A significant portion of meals were below recommended lower limits for energy (83.7%) and carbohydrates (86.8%).
- Children wasted approximately 26% of the energy, 25% of protein, and 29% of carbohydrates from their lunches.
Conclusions:
- School canteen lunches in Porto do not meet established nutritional standards for primary schoolchildren.
- Inadequate food portioning and substantial plate waste contribute to the failure of school lunches to meet nutritional requirements.
- Addressing both serving sizes and food waste is crucial to improve the nutritional quality of school meals.
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