Exploring the link between dietary inflammatory index and sleep disorders: Insights from NHANES and Mendelian randomization approach

Dietary health and sleep disorders are significant global public health concerns. This study aims to explore the potential relationship between the dietary inflammatory index (DII) and sleep disorders, providing insights into how dietary factors may influence sleep quality. We utilized epidemiological data from 24,870 participants in the National Health and Nutrition Examination Survey from 2007 to 2018, employing logistic regression and restricted cubic spline (RCS) analysis to assess the relationship between DII and sleep disorders. Additionally, Mendelian randomization (MR) analysis was conducted to investigate the causal relationships of individual DII components with sleep disorders. Our MR analysis revealed that genetically determined selenium has a protective effect against sleep apnea (odds ratio [OR] = 0.92, 95% confidence intervals [CI] 0.86-0.98, P = .007), while genetically determined vitamin C and monounsaturated fatty acids also demonstrated protective effects against sleep-wake disorders (OR = 0.57, 95% CI 0.33-0.97, P = .039; OR = 0.08, 95% CI 0.01-0.74, P = .026). These findings support the potential role of an anti-inflammatory diet in improving sleep health. Our results also showed that multivariable logistic regression revealed that for each unit increase in DII, the risk of sleep disorders increased by 12.9% (P < .001). After adjusting for age, sex, race, education, household income, hypertension, and diabetes, the risk still increased by 11.2%. Restricted cubic spline analysis indicated a significant nonlinear relationship between DII and sleep disorders. Our study suggests that a higher DII significantly increases the risk of sleep disorders. An anti-inflammatory diet may provide a protective effect, highlighting the importance of dietary adjustments in preventive strategies for sleep-related health issues.