Association between the level of adherence to dietary guidelines and depression among Korean patients with type 2 diabetes mellitus

Objective: This study aimed to examine the cross-sectional association between adherence to dietary guidelines for type 2 diabetes mellitus (T2DM) and depression. Methods: A total of 3457 patients with T2DM were included. Dietary information was obtained using 24-h recall, and adherence to dietary guidelines was estimated using the Korean Diabetes Association-Korean Ministry of Health and Welfare index. Depression was evaluated using a questionnaire. Participants who had responded "yes" to any of the three questions related to diagnosis, current condition, and treatment were defined as depression. Multivariable logistic regression analysis was used to examine the association between adherence to dietary guidelines and depression. Results: T2DM patients with a lower score on adherence to dietary guidelines were more likely to report depression than those with a higher score (Odds ratios (OR): 0.51, 95% Confidence Interval (CI): 0.30-0.87). Patients with poor adherence to moderate calorie consumption (OR: 1.65, 95% CI: 1.07-2.52) and regular meal patterns (OR: 1.69, 95% CI: 1.15-2.50) were more likely to report depression. However, patients with poor adherence to low sodium intake were less likely to report depression (OR: 0.60, 95% CI: 0.40-0.88), and no association was observed between moderate carbohydrate consumption, sufficient vegetable/seaweed consumption, and moderate alcohol consumption and depression. Conclusion: Good adherence to dietary guidelines was closely associated with a lower prevalence of depression among individuals with type 2 diabetes, but the specific guidelines were inconsistent. Systematic and continuous nutrition education for individuals with T2DM is necessary to improve their mental health outcomes.