Daily sodium intake and constipation in US adult males: an uncommon negative association revealed by national health and nutrition examination survey data from the United States (2005-2010)

Background: High sodium intake has been linked to various health outcomes; however, its association with constipation remains unclear, particularly in adult males. This population-based study aimed to investigate the association between daily sodium intake and constipation using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2010.

Methods: Using data from the NHANES database spanning from 2005 to 2010, a cross-sectional study including 7116 adult male participants from the United States was performed to assess the relationship between daily sodium intake and constipation. Multivariable logistic regression models were used, adjusting for various potential confounders, to evaluate this association. Restricted cubic spline (RCS) methods were applied to explore potential nonlinear trends in the association, and subgroup analyses were conducted through forest plots to examine interactions among different subgroups (P for interaction).

Results: The study found that an increase in daily sodium intake was significantly associated with a reduced risk of constipation. Trend analysis indicated a statistically significant trend across all models, where increased daily sodium intake was associated with lower constipation risk, with (OR: 0.78, 95% CI: 0.71 ~ 0.85; P < 0.001) in Model 1; (OR: 0.79, 95% CI: 0.73 ~ 0.87; P < 0.001) in Model 2; and (OR: 0.82, 95% CI: 0.69 ~ 0.97; P = 0.023) in Model 3 (P for trend < 0.05 in all models). On the contrary, RCS analysis did not reveal a nonlinear association between daily sodium intake and constipation risk (P = 0.528). Subgroup analysis further supported a consistent negative association between daily sodium intake and constipation risk across different subgroups, with no significant interactions found (all P values > 0.05).

Conclusions: This study demonstrates a negative association between daily sodium intake and constipation risk among adult males, suggesting that sodium intake might influence intestinal function.