Using smart card technology to monitor the eating habits of children in a school cafeteria: 2. The nutrient contents of all meals chosen by a group of 8- to 11-year-old boys over 78 days

Objective: The aim of the study was to test the abilities of the newly created smart card system to track the nutrient contents of foods chosen over several months by individual diners in a school cafeteria.

Methods: From the food choice and composition of food data sets, an Access database was created encompassing 30 diners (aged 8–11 years), 78 days and eight nutrients. Data were available for a total of 1909 meals.

Results: Based upon population mean values the cohort were clearly choosing meals containing higher than the recommended maximum amounts for sugar and lower than the recommended minimum amounts of fibre, iron and vitamin A. Protein and vitamin C contents of meals chosen were well above minimum requirements. Over the 1909 meals, nutrient requirements were met 41% of the time.

Conclusions: The system created was very effective at continually monitoring food choices of individual diners over limitless time. The data generated raised questions on the common practice of presenting nutrient intakes as population mean values calculated over a few days. The impact of heavily fortified foods on such studies in general is discussed.