Abstract
Previous studies have established a correlation between dietary vitamin intake and constipation. However, research specifically addressing the relationship between vitamin B2 and constipation is scarce. This study aims to explore the link between chronic constipation and dietary vitamin B2 intake among adults participating in the National Health and Nutrition Examination Survey. Data from 5134 participants aged 20 years and older, collected during the 2009 to 2010 National Health and Nutrition Examination Survey, were analyzed. Dietary information was gathered through a 24-hour dietary recall. Participants who reported constipation "always," "most of the time," or "sometimes" in the past 12 months were categorized as having constipation. The relationship between dietary vitamin B2 intake and chronic constipation was assessed through various statistical methods, including multivariate logistic regression, restricted cubic spline regression, subgroup analysis, curve-fitting, and inflection point analysis. The adjusted multivariate logistic regression model indicated an association between vitamin B2 intake and a reduced risk of constipation (OR = 0.78, 95% CI: 0.71-0.87, P < .001). Restricted cubic spline regression revealed a nonlinear relationship between vitamin B2 intake and constipation risk. Inflection point analysis determined that the risk of chronic constipation decreased as vitamin B2 intake increased up to a daily intake of 1.849 mg, with this decrease being statistically significant (P < .01). Above this threshold, the association was not statistically significant. This study demonstrates a negative correlation between dietary vitamin B2 intake and chronic constipation. Specifically, an increase in vitamin B2 intake up to a certain level appears to reduce the risk of chronic constipation. However, the role of vitamin B2 intake beyond this threshold requires further investigation.