Association of dietary inflammatory index with constipation: Evidence from the National Health and Nutrition Examination Survey.

The association of dietary inflammatory index (DII) with constipation has not been well studied in general population. Therefore, the aim of this cross-sectional study was to investigate whether DII is associated with constipation in a large representative sample of the US population. Data were obtained from the 2005-2010 National Health and Nutrition Examination Survey (NHANES). A total of 12,308 participants aged ≥20 years were included in the analysis. DII was calculated based on a single 24-h dietary recall, and constipation was defined as having fewer than three bowel movements per week by the questionnaire on bowel health. Logistic regression analysis demonstrated a significant positive association between DII score and constipation, with each unit increase in DII score associated with a 20% increase in constipation risk (95% CI: 1.13-1.28). Subgroup analysis revealed high odds ratios (ORs) among individuals classified as "Other Race" (OR: 1.42, 95% CI: 1.12-1.80) and "Non-Hispanic White" (OR: 1.31, 95% CI: 1.12-1.54). In addition, RCS analysis indicated a nonlinear relationship between DII and constipation among individuals with a BMI less than 25 (OR: 1.17, 95% CI: 1.07-1.28), while the overall trend remained positive correlation (OR: 1.20, 95% CI: 1.10-1.31). Briefly, our study suggests that there may be a link between DII and constipation, which has implications for the development of dietary interventions aimed at preventing and managing constipation. However, this association was complex and variable depending on individual factors such as BMI and racial background and needed to establish longitudinal studies to confirm the underlying mechanisms between DII and constipation.