Patterns of Ultra-Processed Food Consumption in a Gluten-Free Diet: A Target for Nutritional Intervention

Background/Objectives: Celiac disease (CD) is a complex multifactorial disorder driven by genetic susceptibility and environmental triggers, with ultra-processed foods (UPFs) acting as potential disruptors of immune homeostasis. This study aimed to characterize the patterns and temporality of UPF consumption in a pediatric population with CD to provide evidence-based insights that can optimize the nutritional quality of a gluten-free diet (GFD) beyond mere gluten avoidance. Methods: A total of 128 children aged 5-14 years were enrolled, comprising a baseline cohort of 48 children newly diagnosed with CD (pre-GFD), 88 patients who had followed a GFD for at least 6 months (post-GFD), including 44 participants from the pre-GFD cohort prospectively re-evaluated after 12 months and 44 additional patients with established GFD adherence and a control group of 36 healthy children (CTRL). Dietary intake was assessed using three-day 24 h recalls. Food processing levels were determined using the NOVA classification system, and adherence to the Mediterranean Diet was evaluated via the KIDMED index. Results: At baseline, UPFs (NOVA 4) were the primary daily energy source for both celiac patients and controls, accounting for over 57% of total caloric intake, peaking during breakfast (~74%) and afternoon snacks (~81%). Longitudinal analysis showed that the nutritional profile and global UPF consumption remained remarkably stable after 12 months on a GFD, though a significant increase in vitamin B6 intake was observed (0.9 ± 0.4 vs. 1.1 ± 0.5 mg; p = 0.034). However, meal-pattern shifts occurred over the 12 months: celiac children significantly reduced their daily intake of culinary ingredients (NOVA 2; p = 0.029) and processed foods (NOVA 3; p = 0.025). Compared to healthy controls, post-GFD patients exhibited significantly lower Vitamin D intakes (4.6 ± 9.4 vs. 6.2 ± 12.3 µg/day; p = 0.008), meeting only 30.8% of the reference intake. Both groups presented inadequate intakes of iron, calcium, folate, magnesium, and zinc. Conclusions: Pediatric celiac patients exhibit a high, deeply ingrained consumption of UPFs that mirrors healthy controls and persists 12 months after starting a GFD. While the GFD alters meal processing dynamics, it fails to resolve baseline micronutrient insufficiencies and is associated with lower dietary vitamin D intake, highlighting the urgent need for targeted nutritional interventions that focus on whole food quality rather than just gluten elimination.