Abstract
In France, school meals must comply with 15 frequency criteria (FC) expressed as nutritional requirements (e.g., "starters containing more than 15% fat served no more than four times out of 20") in a series of 20 consecutive meals. The objective was to assess, for the first time, the nutritional impact of complying with French school food FC. Based on 40 series of meals actually served in primary schools ("observed series"), several scenarios (1600 series per scenario) of compliance or non-compliance with FC were simulated, and nutritional quality was assessed via the mean adequacy ratio (MAR/2000 kcal). In the observed series, only 9.7 FC on average (range 4-14) were fulfilled. In the simulated series: (i) MAR was positively associated with FC compliance level, with the highest MAR obtained with complete compliance; (ii) MAR decreased when meat or fish-based dishes were replaced by dishes without meat or fish; and (iii) removing the protein dish without replacement led to the lowest MAR. This study demonstrates that French school food guidelines ensure good nutritional quality of food services. It also shows that generalizing the service of meals without meat or fish would deteriorate overall nutritional quality, highlighting the need to define the composition of vegetarian dishes and their frequency of service to children.