Abstract
Background: Nutritional psychoeducation is a core component of multidisciplinary treatment for anorexia nervosa, yet evidence on its association with changes in eating behavior beyond weight outcomes remains limited. Methods: This pre-post observational study included 45 patients with anorexia nervosa attending a Day Hospital program who participated in a structured, group-based nutritional psychoeducational intervention as part of standard multidisciplinary care. Nutritional knowledge, dietary rules, eating behaviors, food group exposure assessed by a Food Frequency Questionnaire (FFQ), and body mass index (BMI) were evaluated before and after the intervention. Pre-post changes were examined using paired statistical tests with Holm correction. Associations between changes in cognitive-nutritional variables and eating behavior were explored using correlations and multiple linear regression models. Results: Significant pre-post improvements were observed in nutritional knowledge and reductions in rigid dietary rules. Eating behavior showed specific changes, with increased exposure to carbohydrate- and fat-containing foods, as well as improved meal adequacy. BMI increased during the observation period, consistent with expected outcomes of Day Hospital treatment. Changes in nutrient-related knowledge were positively associated with changes in dietary fat exposure, independent of baseline BMI and changes in dietary rules, whereas no comparable association was observed for carbohydrate exposure. Conclusions: In this Day Hospital sample, participation in a group-based nutritional psychoeducational program within a multidisciplinary treatment context was associated with specific changes in eating behavior alongside cognitive-nutritional changes and weight gain. The observed association between nutrient-related knowledge and dietary fat exposure may suggest the relevance of assessing food-specific behaviors and cognitive-nutritional processes as complementary outcomes during treatment for anorexia nervosa.