Development and validity testing of the Canadian Food Scoring System (CFSS), a nutrient profile model based on the recommendations of Canada’s food guide 2019

Canada's food guide (CFG) 2019 provides dietary guidance for all Canadians; however, there is no tool available to help Canadians easily determine how individual foods align with CFG. Therefore, the objectives of this study were (1) to develop a nutrient profile model, Canadian Food Scoring System (CFSS), to rank the healthfulness of individual foods according to the recommendations of CFG; and (2) to assess its validity. The CFSS was developed based on CFG, leveraging existing Canadian labelling regulations to set quantitative criteria to the CFG recommendations. The CFSS included three main steps: (1) classifying foods into the CFG-based food categories and assigning points based on the alignment with the recommendations; (2) deducting points based on the levels of saturated fat, sugars, and sodium using thresholds from Canadian front-of-pack labelling regulations; and (3) calculating the final score from the first two steps to classify foods into one of five categories: "very poor", "poor", "fair", "good", or "excellent" choice. Convergent validity was assessed by examining the alignment of the CFSS with Health Canada's CFG-Food Classification System using a national food composition database and the Healthy Eating Food Index-2019 using nationally representative dietary intake survey data. The CFSS showed strong correlation with the CFG-Food Classification System (ρ=0.782, p<0.001) and moderate correlation with the Healthy Eating Food Index-2019 (r=0.636, p<0.001), indicating good convergent validity both at the food and dietary level. The newly developed CFSS can assess the alignment of individual foods with CFG, which can be used to help Canadians more easily make healthy food choices.