## 3 Results  
The baseline characteristics of the study sample are shown in Table 1. A total of 58 children with CD participated in the study (mean age 8.6 \(\pm\) 4.1 years). A total of 18 participants (i.e., 31% of participants (mean age: 5.7 \(\pm\) 3.8 years)) with CD followed a GFD for less than 6 months. A total of 37 participants (i.e., 64% of participants (mean age: 10.1 \(\pm\) 3.4 years)) with CD followed a GFD for less than 12 months. Three children followed a GFD for more than 6 months and less than 12 months. Among the 58 children included in this study, 41 participants had valid data in terms of the three-day food record and, therefore, the UPF consumption. The mean % of the total energy from UPFs was 47.3%. Differences in the quality of life total scores and quality of life domains between the children with CD who followed a GFD for \(<\)6 m (n = 18) versus children with CD who followed a GFD for \(>\)12 m (n = 37) are shown in Figure 1. After adjusting for age, sex and parental working status, the children who followed a GFD for \(>\)12 m had higher limitations than those who spent less time on a GFD (GFD \(<\) 6 m) (\(p\) = 0.010). The linear regression analysis assessing the quality of life total scores, quality of life domains, and the % of the total energy from UPFs among the children with CD is shown in Figure 2. After adjusting for sex, age, the number of months following a GFD, and parental working status, a greater intake of energy from UPFs was related to greater limitations (\(\beta\) = \(-\)0.380, \(p\) = 0.032). The differences in the quality of life total scores and quality of life domains between the children with CD based on the percentage of the energy intake from UPFs (n = 41) are shown in Figure 3. Those children with CD whose % of total energy from UPFs was above 50% presented (n = 16) with more limitations (\(p\) = 0.019) and inadequate treatment (\(p\) = 0.019) compared to their counterparts (n = 25). Although it was non-significant, the children with CD who consumed more than 50% of their total energy from UPFs had lower quality of life total scores than their counterparts (\(p\) = 0.067). Figure 1: Quality of life total scores and quality of life domains between children with celiac disease following a gluten-free diet for less than 6 months (n = 18) versus children with celiac disease following a gluten-free diet for more than 12 months (n = 37). (**A**). Differences between children with celiac disease following a gluten-free diet for less than 6 months versus children with celiac disease following a gluten-free diet for more than 12 months in the limitations subscale. (**B**). Differences between children with celiac disease following a gluten-free diet for less than 6 months versus children with celiac disease following a gluten-free diet for more than 12 months in the dysphagia subscale. (**C**). Differences between children with celiac disease following a gluten-free diet for less than 6 months versus children with celiac disease following a gluten-free diet for more than 12 months in health concerns subscale. (**D**). Differences between children with celiac disease following a gluten-free diet for less than 6 months versus children with celiac disease following a gluten-free diet for more than 12 months in the inadequate treatment subscale. (**E**). Differences between children with celiac disease following a gluten-free diet for less than 6 months versus children with celiac disease following a gluten-free diet for more than 12 months in the total quality of life. Values shown as the marginal mean (standard error of the mean). Model adjusted for age, sex, and parental working status. CD-QOL, celiac disease-related quality of life (QOL). Greater scores indicate a better perception of each CD-QOL item (e.g., greater scores for the limitations subscale indicate lower self-perceived limitations).