Nutrients, Diet Quality, and Dietary Patterns in Patients with Inflammatory Bowel Disease: A Comparative Analysis

(1) Background: Diet plays an important role in the development of inflammatory bowel disease (IBD). There are a number of methods available to assess the diets of patients with IBD, including nutrients, dietary patterns, and various appraisal tools of diet quality. However, research on diet quality and dietary patterns in IBD populations is limited, and comparative evaluations of dietary intake in patients with IBD have not been performed. (2) Objectives: The aim of this study was to assess nutrients, the dietary patterns, and diet quality of patients with IBD and to investigate the relationship between dietary patterns, diet quality, and the adequacy of nutrient intake. (3) Methods: Three-day food records of 268 patients with ulcerative colitis (UC) and 126 patients with Crohn's disease (CD) were collected to estimate nutrients and food groups, while dietary quality was assessed using the Dietary Inflammation Index (DII) and Mediterranean Diet Score (MDS). Dietary patterns were derived using principal component analysis (PCA). Participants' nutrient intake, diet quality, and dietary patterns were compared. We used binary logistic regression to assess the relationship between dietary patterns (independent variable) and nutritional adequacy (dependent variable). (4) Results: In our sample, patients had inadequate energy, protein, and dietary fiber intake compared with Reference Nutrient Intake (RNI). Regarding micronutrients, intakes of potassium, zinc, selenium, vitamin A, vitamin C, vitamin E, sodium, calcium, iron, niacin, thiamin, and riboflavin were inadequate. Regarding food groups, the highest intakes were fruits, legumes, dairy products, and nuts. PCA revealed four dietary patterns, namely DP1, DP2, DP3, and DP4. Among UC patients, 96, 55, 69, and 48 patients adhered to DP1, DP2, DP3, and DP4 dietary patterns, respectively. Among CD patients, 41, 31, 34, and 20 patients complied with the dietary patterns of DP1, DP2, DP3, and DP4, respectively. There was no significant difference in dietary patterns between UC and CD patients. Compared with DP4 (high intake of mixed legumes and low intake of tubers), DP1 (high intake of cereals, tubers, vegetables and eggs) was more likely to ensure adequate intake of energy (OR, 2.96; 95% CI, 1.55, 5.62), protein (OR, 2.05; 95% CI, 1.06, 3.96), carbohydrates (OR, 3.55; 95% CI, 1.51, 6.59), thiamine (OR, 2.59; 95% CI, 1.36,4.93), niacin (OR, 2.75; 95% CI, 1.39, 5.42), phosphorus (OR, 2.04; 95% CI, 1.08, 3.85), zinc (OR, 2.43; 95% CI, 1.28, 4.63), and manganese (OR, 3.10; 95% CI, 1.60, 5.90), and DP2 (high intake of fruits, poultry, aquatic products, and nuts) was more likely to meet niacin requirements than DP4 (OR, 2.65; 95% CI, 1.28, 5.48). (5) Conclusion: This study clarifies our understanding of dietary intake, diet quality, and dietary patterns in adult patients with IBD. Future attention is needed to improve diet quality, emphasizing the importance of assessing and understanding patient dietary habits and increasing understanding of the factors that influence dietary intake in IBD in order to achieve optimal outcomes for patients with IBD.